I'm a bit of a sucker for cat photos... my two daughters worked me into it
Having had cats for many years I come to believe they have at least some sort of innate indigenous sense of humour. The things they do, the faces they put on - albeit unintentionally - is a source for joy.
The thing with cat-photos, or cat-videos, are that; either you love them, or either you hate them with a passion. Few people seem to be just indifferent about them.