I've been to many many festivals. In fact, I own a business where we are vending at festivals every weekend during the summer, and spend a lot of my spare time going to festivals and concerts.
"Bonnaroo" wasn't searching vehicles, it was the Manchester police department. They were right at the entrance . I only saw this last year. They were randomly asking if they could search. We were the only rv they asked for a while. I wanted to say no, but something told me to comply. Since I was ahem, 99% clean, I consented. They were nice, but doing it for the money. I heard they gave out some fines for illegal drugs. I'm sure some people were arrested.
You gotta expect it, anyway, with 80,000 people! I'm not saying it is right, but odds are that someone's doing something they will get caught at, and get arrested, with that many people.
I mean the beauty of it is that such an event even happens with all those people in one place, where there is basically no crowd control except for some mounted security who are really nice.
About water: You can most certainly bring water to the stages! I carried water bottles in my backpack all day every day. You can take all you want into Centeroo (supposed to be sealed) and then there are water stations at which to refill- and the water is actually good. I didn't drink any of the water in the campgrounds, but Centeroo water was good, really. I take food in, too. You can take all kinds of stuff into Centeroo, but you are right- no coolers. That rule is fine, anyway.
Last year was NOT the worst in my opinion. I have preferred other headliner bands, but all around last year was better operation-wise. (Radiohead rocked, too, and I was never into them before then.) They are perfecting the huge festival, and it shows.
Man, at a gargantuan festival like Bonnaroo, it is what you make of it. Granted you can't control everything, but it sure is a good time anyway/because of it.
The ticket price is not insane when you consider all the bands and entertainment they have at Bonnaroo. IMO, it's worth it. There is music for anyone and everyone at Bonnaroo. I tell my non-music lover friends that it is like Disneyworld for music lovers.
Superfly is the company that puts on Bonnaroo, and they aren't really corporate crap. They are a homegrown company that has the balls and money to put on a great festival with great music. Read up on them if you want. There really aren't advertisements and crap everywhere, Bonnaroo has a logo, and they are capitalists, if that is what you mean.
/end rant