Wifi in public parks.

I have no knowledge on the subject, and I hope many of you can enlighten me as to how wifi works.

I have been in some private parks, and wifi is dismal, but why?

Is it really possible to provide a signal over a campground, or are we just talking about people taking their devices to a confined area where the signal is strong?

I have used a signal booster before with great success, but the same question.. Will everyone using a booster just jam the system again, or can the park provide enough "I think it's bandwidth?" that will enable users?

And then lastly.. is there any way that might enable certain sites to have access for a period of time, then the access moves on to other sites.. so that instead of a jam, there really is good access for a short period, but you have to know your time?

this should be interesting.. thanks. Mike