Since I was a kid, I failed so hard at being a guy. I've always been hopeless at athletics. My body type has always been pretty meek (let me not doxx myself and say more). I hate any sort of competitive environment. I can't hold my liquor for shit. I have a very high pitched voice and an expressive way of talking. Friends have described my voice as a "gay twang". My mum probably assumed that I was gay from day one, as I got a lot of "it's OK to be gay" from her growing up. Sadly I had too much soy or not enough soy, because I grew up attracted to women.
Maybe you old comrades remember, but schools in the 90s were full of homophobia. "That's so gay" criticised any action that deviated from some masculine ideal. I got this multiple times a day, and I learned to stifle my personality to avoid the rebuke of my male non-friends. I'm not even complaining, there's so so many that had it way worse than I did.
Nowadays it's great being a flamboyant straight dude. I can be as sweet, as empathetic, and as expressive as I want. I have cute and colourful clothing. I get really ecstatic around animals. I cry. People like me for being fun and engaged with stuff. Nowadays if some guy colleague says that's "gay" it's like 
"are you alright mate??"
I did go some LGBT events and actions in the past, but not a lot. If I do anything positive, it's to enforce no homophobic language with my students, which guys has gotten a lot easier in the past 20 years. Really, the kids nowadays are much better than we were. OK, I have hooked up with a few dudes here and there, but it feels like stolen valour to call myself bi.
So thanks a whole lot to all the queer people who have made my life much easier, when I've done so little.
I imagine the labels are as valuable as they are useful: "Oh, you're bi? Are you looking for a man to date? Oh not really?" It must be different if you're discovering yourself with them and I have no personal reference for it.
Straight is the only special label that you need to perform and maintain where you claim to be straight , yet you drink pink lemonade and wrestle
. I might need more education than what TC69 left me with, but I think of stolen valor as more of an attitude. The difference between a straight ally and a bi ally is much less than a straight/bi person who shouts and hollers about how we're so close, wonderful, and superficially powerful.
It's probably a really sticky matrix because you could have an ally who has read Marx but does very little, but you could have an ally who thinks that Isntreal is the LGBT bastion in the middle east, but shows up every time they're needed. You could have someone who is trying the labels as a costume, but you know they need help and guidance and you could have someone who is pretty sure they're straight. In my estimation it comes back to organizing and taking the requisite parts of theory into the situation so you don't get co-opted by unfocused action. Not that you're not having fun, meeting new people, or being silly while you're there, but when it comes to social causes, are you there liberating or fueling the machine?