@Background Pony #CE2F  
@KillerKid86
 
Really? Because it seems like, if you payed even the SLIGHTEST bit of attention, the majority is the opposite. People list their reasons and actually completely shutdown statements like this with reasoning and facts.
 
But instead when people make blanketed statements like these it seems people like you immediately jump on the bandwagon and go “Yeah, that’s Bronies!” without looking at what anyone else has said or done outside of only what you want to see.
 
Now, I would agree with you if the majority of bronies acted like hypocrites…but they don’t. If anything they over analyze the SHIT out of everything and frankly nitpick just a little too much when something contradicts something previously established, IMHO. When you are dealing with people that basically have OCD and know everything about the show down to the littlest detail, it stands to reason that maybe just some of these overtly obsessed people might know something about what they’re talking about when they go into such detail on the subject.
 
I’m not one of these people, but at least I can go out of my way to research a talking point before I open my mouth and make misleading or untrue statements…and if I do, I at least correct myself and apologize.

One more reason I think why people are more willing to accept MarbleMac as opposed to Flashlight, is that it seens to serves the plot, instead of feeling like it was put in to appeal to a tween audience. The attraction is there to go along with the rest of the Apples coming closer to the Pies during their visit, which is a big part of the episode. And Marble and Big Mac are the only two characters there who are really open for anything like a romantic involvement; Granny Smith is too old, Apple Bloom is too young, and Applejack is a main character. Not to mention that Marble and Mac were the only opposite-sex pairing there, and unfortunately the show doesn’t seem to be willing to put explicit same-sex couples on screen.
 
Contrast that to Flashlight which, as I said, seems to be in EqG in order to appeal to the target audience as opposed to coming naturally from the story. Couple all of this with the multitude of other reasons people have given in the comments here, and it seems pretty clear to me why people are far more willing to accept MarbleMac.

@Background Pony #CE2F  
Don’t know if you mean this or not.
 
Either way, it’s true.

My God, we Bronies are SUCH hypocrites

I agree with this.

@Appel  
Except the blushing and the flirting…seriously, this comment from a BG sums everything up perfectly.
 
@Background Pony #05F6
 
This is what people have a problem with Flashlight.

@Soarinjack  
Doesn’t that bring us back where we started?

@Scrounge  
Then again, all shipping is subjective.

@Appel
 
I think Marblemac is based mainly on “They’re cute together”, which is admittedly subjective.

Quack, Quack everywhere!

@Starswirl  
Much less, IMO.

@Starswirl  
I don’t know that there even is another EQG movie in the making. It would be neat, though. But human Twilight hasn’t shown any interest in Flash… so, I doubt it.

@Starswirl  
Marble’s entire personality is “shy and says nothing”. There. I summed her up. She’s perfect waifu bait, to be sure, but Flash Sentry at least has a good resume of being a person.
 
Hell, some people say he’s helping Twilight in the first movie for no reason, but he was Sunset’s ex, so there’s nothing to suggest he KNOWS she’s up to something and wants to get back at the bitch who broke his heart (since I assume he had feelings for her back then). I’m not saying FlashLight is a solid ship, but it definitely has more moments to go on than MarbleMac (and FlutterMac, I have to mention) does.

@Appel
 
@ChuymaruZ  
I wonder. If the next film would have Flash Sentry hooking up with Human!Twilight Sparkle, would people be less pissed, or more?

@ChuymaruZ  
I hadn’t accounted for that. The butthurt is real.
 
I should draw some FlashLight just for fun.

What’s more ironic is, I think, the fact that Marble Pie has fewer distinct personality traits than Flash Sentry.

@ChuymaruZ  
Nah, it’s getting downvotes because it’s a dumb attempt to cause drama.

@Appel  
because this pic shows us the hypocrisy of the fandom and people dont like that

I don’t get the downvotes. Other than people being sour and biased.

@Background Pony #05F6  
Yeah, that seems about right. :U

Marble and Big Mac have significant traits in common, beyond just circumstance and shared experiences. Flash and Twilight don’t.
 
They both have established personalities that extend beyond their role in the story. Flash doesn’t.
 
They both remained in character when showing interest in each other. That definitely can’t be said for Twilight’s interest in Flash.
 
And finally, their potential romance is delivered subtly, without being the sole purpose of either character. That can only be said for Flashlight if you spell “subtly” like this:  

It seemed out of character for twilight to rush to romance like that tho

@Mr. Market  
That’s wut I’m sayin’!

I’ll assume sarcasm with the topic placed, and then add my two cents:
 
Marble x Mac = More plausible than most other ships by far in the fandom since they’re not BG characters, but a recurring supporting character and one supporting character related to Pinkie. We know about Marble just as much if not more than most BG characters, so I think she deserves a fair shot. Distant possible cousins getting together… It’s WAY more likely than you think. And they seemed to like each other in a bashful way, which is more than I can say for any other mare that spent time with BM in the show. Remember Cherilee? She wasn’t all that interested, and she was swooned later on by Flutterguy’s singing but even then she didn’t follow up on it; Cute crush material at least.
 
Flash x Twilight = Ho boy! Here I go…! I’m not gonna pretend to be an expert on romance, but the whole thing just plain lacked chemistry. I don’t even think Flash is terrible, but I never once felt convinced they were a thing in the movie, and I tried, I mean really tried to be accepting. And I WOULD say it was a cute crush, buuuuut… What DOES Twilight see in him? Maybe she’s plain odd and likes aliens? She never saw humans before, and she’s still horse gal deep down, so… What did he ever have going for him that NO OTHER STALLION ever had for the bookish nerd? Like, legit, if someone wants to tell me off for whatever reason, I’d like to know what was supposed to convince me in the first movie, cause every other appearance either had LESS chemistry or it was non-existent.

@Toonboy1029  
ummm… this… I guess…