We used to do something like that, except later. After a certain time here, the parks and grass trails are populated by smokers. I see people blazing behind bushes or on benches all the time. I personally think it's too sketched, as I've had to dip out and haul ass so many times.
I was a friend of a stoner frat at William & Mary back in the early 90's. We used to have events that we called ounce blitzes. Growers that were friendly with the group would sell us pounds of nugget for about $1000 (charity thing). We would invite about 100 people over at 10 am on a Saturday. As I recall everyone would put in about $5 (might have been $10), and we would get as much smoke as we could. Usually it ended up being about a pound. We then twisted the entire pound up into exactly one more joint than there were people. We would close all the windows, lock all the doors, and light all the joints at the same time. The only rule was that id someone handed you a joint, you had to hit it. 1 pound gone in 10 minutes flat. We'd be high for the entire day and night. I forget what the point was (I think it was originally done with just an ounce, around campus as a form of protest), but is sure was a blast. I actually quit a job to attend one of them.
I love hearing about all these crazy fairs like Comfest and Hempfest. Are there any other crazy festivals or celebrations that are worth a lit roadtrip?