I think it depends on what you want to get out of the match as well. Or, what the goal is, I mean. I started shooting matches not long after I started carrying. I started because I wanted to be as competent as possible with my weapon. Because of this, I wasn't out buying competition holsters, or other fancy things. I didn't make fun of the guys with speed rigs or stuff, because thats what they are there for, to get better at competing. To be honest, like Kurt said can happen, I learned some things from the gamers to apply in carrying, and being up against gamers made me push my self to be faster and better just because of my own competitive nature.
In the matches I have shot with my AR you see the same things, but magnified to a whole new scale. My AR is my house gun. It has a light on it, and at times has had other stupid stuff on it, that I later decided was not needed. My gear was what was cheap, and available locally. I had a thigh rig to carry my spare mags in, and a kydex single mag pouch on my belt. ATAS? yeah I got called that when I posted a vid, but I didn't care because it served my purpose. I have one AR, and can't afford a second to set up just for matches.
So it comes down more to your own ideas than it does those of the people around you. I had one guy make fun of my stuff when I was at a match, he is an instructor at USSA and I hope has changed his attitude. He had more money in his AR than I have in all my guns combined. Oh well, I kicked his but so lots of good it did him.
I shoot for fun, I shoot matches for fun, and to learn from people who do it more often than me. There are some jerks around, but for the most part the people who I have shot with are great.