Because what the person is really saying is NOT that there are no vanities, regardless of the actual words he used. There are plenty of vanities. There are new vanities with all the biggish events. So it is not true that there are no vanities.
He just means that there are no super rare vanities that he can get for cheap that no one else will overbid him on. So what he really wants is a rare vanity that only he and a few people get, but which is affordable for him.
Because if it was a common vanity, then it would be "no" vanity.
js.
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