I go on residential trips a lot - school trips, Duke of Edinburgh and Guides. On all three we wind down with a glass or two of wine at the end of the day, once the children have gone to bed.
No-one gets drunk on any of the occasions. On school trips/D of E there is always someone who doesn't drink and is able to drive the minibus (insured by the school) should an emergency occur.
On Guide camp, there is usually someone who doesn't have a drink although it isn't insisted upon. The difference here is that we don't have a minibus and if we drove a child to hospital it would be in our own cars under our own insurance. This opens a whole can of worms should an accident occur en route. Although I could have business insurance, I am not prepared to put myself in this position - we would use an ambulance or taxi.
I don't see the problem with children seeing adults drinking responsibly. It is good for them to see people having one or two drinks and then stopping.
I think it is disgraceful when we get asked to pay towards trips. Most trips I go on are at the weekend or school holidays and I don't get paid. There is some debate whether there should be a contribution to food - I'm on the fence as I think as I would normally be buying food if I were at home, it isn't an added expense, but another part of me thinks free food should be provided as a 'perk' of taking children away without being paid.
My Guides were offered the chance to go on a camp for May half term, Monday - Friday. It sounded fab until I read that leaders had to pay the £150 also, and as well they wouldn't be allowed to do activities but instead would be cooking for the children and cleaning. I may have been tempted if I could have taken my camp chair and relaxed while supervising the children whilst doing activities with instructors. We were not allowed to add a % on to what the children paid to cover our cost. Because of this, my girls are not going as I wasn't prepared to give up my week off to look after children not just for free, but have to pay £150 for the privilege. Instead, myself and my boyfriend have booked a week's camping with the £150 for just the two of us. Bliss.