It's definitely served its purpose: making everyone super horny while lowering their inhibitions. At this point almost everyone has had sex with Sterling and each other, so they probably no longer need the extra push from the AC gas.
I wonder though, if the characters do learn about the gas, will that change how they feel about each other and what they've done?
Hunter has started to vary his tactics, with the wine and with whatever he told Drew about (something specifically affecting biological males).