I don't drink anymore but if I did I would find it inconceivable to turn up for a party/gathering without a bottle of something. I haven't drunk for 7 years but I still get the urge to drop into the bottle shop to grab drinks if I'm on the way to see people.
I hate arriving at someone's house empty handed. Even if they expect nothing I still have an expectation upon myself to brinf something.
Yes but again that is your situation and how you and your friends work. Blondie explained the way it is with her friends and how they normally do their get togethers.