Agreed. Also, closest to the hole gets the pin. First one in picks it up. Dont stand directly behind my line and at least act like you tried to avoid walking on it.
In-group etiquette is much more enforceable; usually by a well-placed passive-aggressive sarcastic comment. It's the group to group stuff that's annoying, because many don't know or don't care or don't care to know.
Example: at my club, my regular foursome was playing, and we play fast. There was a threesome in front, and they were falling drastically behind the group in front of them, such that at the turn, they were 6 holes behind. For you non-golfers, that's Lee leading Bourn around the bases. They had ample opportunities to let us through, but did not. At the 10th tee, they were still teeing off as we arrived. The one member in the group looked at us and asked "Are you three or four?". We said "Four", not adding "Du-uh." He shrugged and drove off.
Three excruciatingly slow holes later, I called the clubhouse and told them to send someone out. The starter came by, we made our point and he, reluctantly, went to talk to the group in front. They sped up (a little), but when they finished the 18th, the member stood and stared us down as we hit up to the green. Apparently, he was with two important clients. They left before I had the chance to tell him in exactly how many ways, and with how many utensils he could go fuck himself.
The point being, adherence to basic etiquette would've avoided any and all ugliness. All that needed to happen was that, when he saw that they were falling behind and holding us up, they speed up or let us play through. Either way no one complains to anyone about anything because it's all good.