I find that they think this is OK and the custom in that area is to share whenever whatever unabated is curious at the least.
In S.C., its just the opposite. You never take anything without being invited, actually it would be very forward to even ask.
The owner is expected to offer in every occasion however.
Transplanted Yankees excepted.
In the Weaz's case it would go like this:
Friends came over and you have a keg. If they asked for some it would be like the worst thing they could do. On the other hand, if you didn't offer, it would be just as bad. it's just plain good manners.
If I was offerd a beer I would take one and even after the "sure, get all you want" I would never get a second draw without the hosts making the offer.
This goes for other situations also. At dinner, the lady of the house is in charge. When there is only one biscuit left and every one is staring at it but no one takes it. That would be the worst manners ever. The "host" would never take it but will offer it to guest first.
Same way with wine. Each gets a glass but never pour a second without it being offered. Everybody is sitting around bugg-eyed wanting another glass, commenting on it, picking it up and reading the label, but won't pour another glass until invited to do so. The host will go to Etiquette Hell if they don't offer another pour.
So at the Tubercule household it goes like this: as soon as guest arrive, get them a mug and introduce them to the kegarator. Keep an eye out and as soon as they get low, a nod of the head and a gesture toward the tap is in order. This goes on constantly and takes dilligence but it is protocol.
Fishing with the buddies? Who(m)ever brought the ice chest full of Millwaukee's Best with all of its hoppy goodness owns it. They offer, you take, they offer, you take, in that order.
Got a neighbor with a broken tractor? You offer to loan him yours, or even better, to bush hog the field for him.
But for a bastard to walk into my house and take MY beer with out asking; he would be ostracized by the community.
That's how we roll.