Sorry not read all the thread.
When my wife and organised our civil partnership we hired a hall, a converted chapel, and had a re-creation of a church tea from the Whitsun Walks when I was small.
As far as drinks were concerned we provided wine and bubbly for a toast when we all arrived at the venue; it was very informal 
Then wine and soft drinks, nice ones, with the meal and juice etc for the children.
In the invite we said Bring your Own, and your mixers and everyone did so cheerfully. It worked really well, was a fantastic day. The children were a feral bunch and had an amazing time, there was live music and a fab disco, with all our favourite songs put together by my BiL, who is knows all there is to know about popular music from the 60s onward.
No-one seemed to mind having to bring drinks, they were able to drop them off at the venue in advance, suitably labelled, but as a few of our friends would certainly have smuggled a bottle of spirits into any paying venue it just eliminated the need for secrecy. 
I have fond memories of one wedding at an hotel with a Master of Ceremonies who urged any guest carrying a present to take it along to the room set aside for the purpose, or even offered to do so himself. He had a right tug-a-war with one of my group, who refused to part company with the shiny bag, bedecked with ribbons that held her supply of rum and Coke.
Having fun with the people you love is the point of the reception, I think people will be happier bringing drinks rather than being charged cash.