Hm, the theme from your experience with themes seems to be that people don't bring alcohol when requested. The part of my brain that handles etiquette basically cannot process this problem at all, sorry.
Maybe get one or two of your really close friends who can handle the explanation, explain it to them, and hope your other friends figure it out by osmosis?
Alternatively, encourage a rotating hosting schedule. Good hosts make good guests.
s/v Laelia - 1978 Pearson 365 ketch
s/v Essorant - 1972 Catalina 27