Another transit advertisement past its "sell by" date

Canada Line SkyTrain, Vancouver, BC (November 22, 2014)

I think that this may be the case of the more you look for something, the more you find it. I keep seeing transit advertisements that are still up long after the event has finished.

In this case the advertisement is only a few weeks out of date, not quite as bad as the advertisement for the "Holiday Gift Fair" that was still up in April.

Bus advertisement for Holiday Gift Fair, Vancouver BC (Still up on April 9, 2007)

But this sort of thing should be more of a concern for both advertisers and the firms selling the ad space. I wonder what it will take to fix this problem?