To be honest I think I may have misinterpreted the goal of this meeting. In some correspondences it's actually referred to as "having a drink", singular, and while I'd imagine that there isn't a set-in-stone upper limit, I don't think we're going there to get shitfaced. It'll be me, one guy I know slightly, and a few of his friends that I don't know at all. I'm a lightweight (2 beers over an hour or two will easily get me a bit tipsy) so I'm hoping $20 is sufficient.
And just so you know, some of their infractions involved a meat cooler being at room temperature, mold growth in the taps, and spoiled food. Not your run of the mill dented cans or insufficient lighting.