Women with big bums know that their bums are big but hope that they are not as big as they think...which is why they ask and then accept the lie which is then told to them in response!
Men who do the comb-over are living in the vain hope that 3 strands of hair across a bald head equals 'not bald!' This too is a lie.
As for the cat food - personally, although I have not and never will taste it, I think that Felix cat food looks much juicier and tastier than Whiskas.So that could also be a lie! Cats eat birds and mice, so I don't think they're so fussy really!