I learned to fly on my own at a local community college, and at a local high school. Mostly speed 400 stuff, but I've had a few hot ones (Twinjet comes to mind). I've never been kicked off, and most people are just curious and interested when I start flying. I've had the cops stop by a few times, but they are generally good natured and say that if no one complains, they don't have a problem with it. (having several friends on the local police force helps too)
The high school as a very old and rusted sign that says "NO POWERD AIRCRAFT", but I think that was aimed more at loud fuel planes. Electrics seem to fare much better in the small fields.
My biggest problem is golfers. I used to leave if a golfer was on the field, but all summer they would show up and start hitting balls in my direction. Two can play that game...now I just fly anyway. I don't do anything stupid, but I only give them as much consideration as they give me...sometimes that not much!
After all, I consider an uncontrolled golfball more danegrous than a controlled airplane...at least I can decide where it goes, more than I can say for most of the golf hacks I see.
In short, play stuipd and keep flyng. Don't argue if they try to kick you out...but a little common sence usually means it would never come to that.