[alttab]

This is an American interpretation. Here in the US, cones, lights, or lane-blockers are used to close exits.

Culturally, its because American's won't read a sign and follow the instructions if we can still "do" it. You have to physically block us, and its too expensive to change all the signs.

[rob74]

Nah, it's actually the same here in Germany too - I live near a railway crossing which was recently rebuilt and couldn't be used for a few weeks. The "strike-through" at the intersection was just the first step, then there was a first barrier blocking half the street, with a sign "residents only", and then a bit later a second barrier, but still some people just absolutely had to drive past all those barriers until they were literally in the middle of the construction site to find out that no, it's really not possible to cross the tracks...

[ceejayoz]

My favorite is Chicago's reversible express lanes, which have thirteen physical gates you have to blow through in order go to the wrong way. I always wonder if they add another set every time someone still drives through them all.

[meheleventyone]

They aren’t closing the exit though as it’s needed so people can get down there for quite a few reasons. There are actual manned roadblocks a bit further in.