After many years of experience, I would advise you not to offer them drinks because there is a good chance your service will not be as good. Their performance will be less enjoyable once they start drinking. They might want to do drugs and talk a lot. Perhaps a lot of them will ask for alcohol because some of them don't like their jobs and need to drink to get that little boost to forget where they are , they also need to remember they are here for business and they need to satisfy the client. It's sad, but it's true.
I mean there's a lot of factors involved, many already mentioned on this thread.
I will say I enjoy having drinks. The best scenario might be,
1. a booking on the later/last part of the girls schedule
2. bigger one is you already are familar with each other from a previous booking.
3. decent wine... $25 and up. You invite a girl who if by chance knows her way around wine and you buy crappy wine... it's not gonna be enjoyed.
(conversely buy nice wine for one who doesn't drink wine and it's a waste, i get it).
I've definitely had girls readily finish my bottle.
4. perhaps a 90min session. this allows for some calm drinking.
I was declined my offer of wine just last evening, however thankfully I've never had it so bad whereby the girl asks me for the alcohol.