Hmm Legality shouldn't be an issue... as long as it's just a bunch of guys meeting up to duel... If we were meeting up to showcase vendors then that might be a problem... It would have to be a saberland swap meet of sorts.
Legality would be a HUGE deal.
I could see a minimum of a 2-3 million dollar event policy as a starting point...that works out to a single payment of $5-8k and $20-30 per person...
This sort of event would draw the best and worst of possibility...there are a lot of true wack jobs out there.
Now a sponsored event with every single person having to be a member of one group or another, established contact with someone who can stand for them...then maybe.
But if you gather 10, 50, or 100 people to conduct light saber duels, something is going to happen.
Not meaning malicious, but rather the potential for slips, trips, falls...opps I'm so sorries...I don't know what happened officer, he just grabbed his chest and slumped over...ahhhh my hand/fingers/eye/etc...and so forth.
A group of 5-10, that is easy to manage and deal with...50-100 now there are some logistics involved...will the event supply water, medial aid, rooms, insurance, where will it be held, permissions needed, laws broken?, is there and age limit, can anyone participate, inspections of equipment, restrictions on equipment (why can't I use my steel rebar saber? it is my practice saber), clothing requirements/restrictions, safety equipment...required? will it be supplied? one size fits all?, weight classes, experience classes, age classes, etc.
I suspect you would need to consider a value of $200-250 per person per day...break this down for a whole event...100 people @$225 = $22,500 minimum cash on hand to pay for sanitation, required fees, setup/cleanup, event location, security/police, ambulance retainer, lawyer retainer, insurance deductible, etc....so a two day event for 100, $45,000 in the kitty.
Now all this is just the way it is...that all said I would be 100% up for being involved and participating.
LARPers get away with it because they use padded and generally safe toys...I had a lawyer friend comment on this very thing when I was live steel training "if you are not willing to be smacked in the head with your tool of choice then it is not even worth considering safe play"
Big foam play weapon, whack hahahahha that was a good one.
Light saber, whack hahahaaoo ah aaah John you ok?...oh no, someone call 911...