New rule on bus?

Usually we will see the sign of:
NO Drinking
NO Eating
and maybe NO Littering on the bus, train, or stations.

There is this bus put a sign of NO Vandalism!

So what is "vandalism", according to en.wikipedia.org/wiki/Vandalism

Vandalism is the conspicuous defacement or destruction of a structure, a symbol
or anything else that goes against the will of the owner/governing body.

But isn't it a common sense for not destroying others property? Then they might as well add in:

NO Pee !

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