If you pull up and stall with 2 guys right behind you, yes, they'll run into you.
If you go HO from 600 out and don't duck, yes, they'll run into you.
If your following right behind someone, and he pulls up and stalls, yes you'll run into him.
It seems to take a while flying to get a feel for it. But I didn't have near the collisions yesterday that I did the day before.
In large part because you learn what activities are going to lead you into one.
Granted they still happen, stuff happens.
The planes are free, come up and try again.
The more you anticipate, watch for collisions, work for good shots without staying glued to his 6 the more fun you'll have.