I included 'no gifts' on the wedding invitation and for the most part got no gifts (the grandmothers couldn't come without a gift lol). We were in Australia at the time and returned to NZ for the wedding, everyone had to travel to the location (in between our hometowns) and we didn't need anything. It meant a lot to me that people would travel to share our day. We subsidised the accommodation and helped out with petrol for some as I know that it was expensive for people to come. I certainly didn't expect or want any cash from any of them.

As far as wishing wells, I do see the benefit to them over gifts but I would never guestimate the cph - I would give a standard $50 to any wedding I attended, perhaps more for a sibling or very close friend.