The far more insidious part of (some) advertising is how it makes "consumers" feel about themselves. Poke that little nugget of self-doubt someone carries (because we all do), and then tell them you have just the thing to make it better. You don't even have to be explicit about it; just show them people onto whom they can project not suffering that doubt, and associate those people, and the fantasy of feeling that way too, with your product.

Cha-ching!

EDIT: phrasing.