There was an instance in SandBlast where all the inner collision boundaries of the factories where removed shortly after the start of the game.
This allowed the MA, tanks and mechs to go through the wall going outside, but not from the outside going inside.
The floor also was no-collide, and this made buying stuff really hard. You had to jetpack midair inside the area of the hangar to be able to buy. And landing or going outside while in the menu closed it instantly if you did not bought something yet.
The same issue made it impossible for threaded tanks to go out the "door". You had to go through the wall to leave the hangar.