Neat idea, but the liability is the big issue. My wife and my mother both had "team building" work things in my gameroom, basically no payment, but their company brings the food and drink, and I eat and get loaded for fwee! I didn't care about payment, as I like watching non-pinheads, and seeing which games they seem drawn too. It was interesting.
Talk to your insurance agent, see what is required for you to be insured, and they pay that, on top of whatever else you feel you want, if anything. I might request a certified bartender in the future, as this would (depending on the law of the land), cut out any host liability against you to anyone who is served while at your residence.
Possibly a hold harmless and indemnifying agreement by the company for any possible issues involving injury or death (slip/trip and falls etc.).
Oh our litigious world, it all used to be so easy...