There's no "camping" at the cornucopia, they set up base there. There is no reason to have a base in minecraft as you can hold anything you want, thus the only thing a base is good for is a strategic meeting place.
The center is a strategic stronghold as of now. There is no threat of oncoming attack, the chests resupply your goods and give you diamond armaments later on, making it the "easy win" scenario. That's way too many good things.
In real life it wouldn't be such a great location, the fear of archers and other ranged attacks can kill you in 1 hit, but a team of fully armored and armed minecraft players can play a game of TRYING to get hit with arrows and have no worry of dying.
All positive, no negative.
Here's a graphic for people who don't get it.
Pros:
Free supplies
Wide range of view
No hazards
Control of resupply drop
Cons:
Everyone knows where you are
dimly lit
You don't even have to hold it very long. Just hold it until the resupply, get diamond gear, hunt people down, repeat