Things can change. While it's fun to poke fun at each other - you know, what make/model of frame, wheelsets, whatever it certainly is no fun when you are intentionally snubbed. I wave to every rider I see. I don't care what they are riding. If you take the same route regularly you'll notice people start to wave back Any attitude is infectious. Wave enough and people will begin to wave back. Be kind and people will remember you were kind and some will even be kind to someone else. It's the long game.
Some things people bring on themselves when they play into stereotypes. For example, I don't bat an eyelash when I see some young guy covered in tats and crap pierced into his face - look anyway you like - but there are plenty in my generation who simply will not abide such appearances. Don't complain - you got exactly what you wanted.
Same goes for people who decide to behave like idiots on their bikes because they think it's cool. Need a reference? Watch any video of fixed gear riders in public. Again, don't whine - you're getting exactly what you want.
Want people to treat you well? First, behave well. That's on and off the bike. I have yet to have anyone treat me negatively because of the type of bicycle I ride and any questions I've gotten are all good natured or questions of genuine curiosity. How can that be? I live in a major city. My ass is in a saddle every single day of my life (well, for all intents and purposes). I ride to commute, shop, general travel and for the joy of riding. I'm never mistreated. Ever. Of course I'm not counting how vehicles behave. I mean person to person.
While ass holes exist it is my opinion that 99% of the negativity people claim to experience is either outright contrived (being mistreated is so hip) or brought on by the way you behave. Stop lying and/or behave in a manner that wouldn't make your mother wince and you will cease to pretend to be mistreated/truly be mistreated by 99.9% of the population.
It's all up to you. Your call. It's not the rest of the world - it's you. (Oh, just to be clear, I'm also a "you".)