I think that grilling out would be an awesome idea, maybe grill during normal eating hours (away from peak tourny times) and have a $5 all you can eat burger/hot dog session for dinner. It would be a nice alternative from pizza delivery. Pretty sure you can get large quantities of frozen "burger meat" for such occasions at a local food mart like GFS or something similar.
It would also be nice to get some local restaurants to give us a weekend deal. If we said hey, We're going to have 100+ hungry gamers here for 2 days they may toss up some deals as they would want all that extra business.