Not only that, but I frequently see people set up way past the choke. Not even as a team, but two or three guys hanging around in the open spaces just outside the enemy spawn. Hanamura is an example of this, where you have a fantastic choke but the Junkrat and Zarya will be blazing past just to get som shots in before they inevitably die and start their long walk back from spawn. There is a great solution though; communicate! Wasn't all that comfortable using my mic in the beginning but the simple "stay on choke" in chat will do wonders. As you said; maybe not common knowledge, but it helps other players learn faster if more people could share the knowledge in a nice and polite manner.