It totally depends on the venue.

I've taken my hoop to clubs that had incredible DJs and should have been packed, but there was tooooons of space. And sometimes there's not an inch to move. It is really annoying when you have to go back out or find someplace to store your hoop. And I don't know about you, but I always feel super anxious when my hoop is just stowed behind a bar somewhere. In fact, last time I did that, I came back in to find all these people trying to use my PSI and knocking it into everything! After I had asked them to keep it safe for me.
It also honestly depends on what level you are hooping-wise. I recommend making business cards (you can get them for free from vistaprint.com, just pay shipping). It makes you seem a lot more professional. Definitely call ahead.
On the space and rudeness issue, sometimes I understand. I mean, if I was at a show that I was really excited about and wanted to really get into it, but couldn't because one person was taking massive amounts of space, I would be a little peeved. Honestly, I never, ever hoop in a crowded party space UNLESS I have been asked by the host/DJ/owner to perform. I've always felt it's a little rude to ask people to move for me. I also never hoop in front of a band playing unless they have asked me to or it's just a DJ, because I feel like that draws attention away from the people that everyone came to see.
Good luck and Happy Hooping!

yeah, these asses tried to pull that crap with us and they were never even busy, they banned hoops because they could be a potential weapon, stupid, so we just boycotted that club and then my BF got booked to play and I told, "Well have fun, I am not going for principle sake" they had absolutely no reason to ban hoops when for months before they were fine and there were never any problems with bringing the hoops, well the DJ putting on this particular night got the okay, door guy tries to give me shit and say, well, we will see if we will allow them or not tonight on how the night goes, a real dick he was being. I looked at him and said, Buddy, it's called hoop etiquette, we LOVE our hoops, respect our hoops and therefore will not allow any jackass to disrespect our hoops, well, the night was fine and few weeks later we go back and the attitude of door dude had totally changed and he was real cool with us, and now months later no one goes there anymore, cuz the owner's blow and all that is is straight up karma, we much prefer our regular spot where our security "steals" our hoops all night so those big bad boys can hoop themselves, gotta love it, we are the only spot whose security hoops it up all night with us ;-)

I only saw two girls carrying hoops at Coachella that year. I believe they were affiliated w/ Lucent Dossier. They weren't actually performing with the hoops, just kind of wandering.

Yeah, security at festivals tend to not know what's going on. I haven't had a problem with hoops at any fest, but anytime I get a security guy that says no to anything I want to bring in, I just turn around and go through a different line and get right in.

Yep, happened to me too on the morning of the second day (Friday) after I had been hooping inside on the first night. I could see people hooping so I went off on "security/gate checker". I told him I had been in there the night before, hooping all over the place and at the SuperHooper workshop and that I could see hoopers from where we were standing. I also pointed out the fact that the frisbees being thrown around were more dangerous than a hoop. The guy behind piped up in my defense (I have no idea who he was) and I guess the security dude kind of gave up cause he said "Talk to him" and pointed to the head security guy at the gate. That guy said, "Hoops? Good grief, yes." No more problems after that with getting the hoop in.