I'll just share my experience:
Personally, I've been playing for 3-4 years on and off, and I've seen all types of people with all kinds of attitudes, some are friendly, some are serious, some are playing or goofing around, some are just not acceptable due to very bad attitude etc.
Just wanted to share my experience, not really saying anything but:
1) I've just started doing squats last year..therefore i still need to work on my form..usually i will do a parallel squat, some of the senior guys there always tell me to full squat but what I always saw they do is half squat..which really makes me wonder y?
2) I'm regular at this gym..i've just finish my sets..so i sit on the bench for a while guiding my friend to do deadlift, however come this two unknown guys with that rude-kind-of-look staring at me, after a while they didn't talk but only pointed to me to use the bench..for me personally i've no problem as I don't use it anymore, but please, can you just said in a very polite manner, using words, to ask? Later on I just saw that they are doing sets of bench press and they still give that rude-kind-of-look (unfriendly look)..and although they are bigger than me, they still can't beat my bench poundages, and I don't have that kind-of-look.. seriously...
Sometimes, people just are born with a naturally unfriendly face. I'm one of those people. However, I do make it a point to be courteous and well-manners when I wanna share a bench or dumbbells with someone. So far, everyone has been nice enough to share. However, there are a couple of douches who rather not share and waste 30 minutes hogging it with a 5 min break in between every set. Sigh.