> Everyone is influenced by advertising even if it’s third hand

Expanding on this.

"Wanna go eat somewhere? Like McDonald's or something?" -> McDonald's is suggested offhandedly[1], but that's only because it's already somewhere in the back of the person's mind, and it's already associated with "eating". It's only "already" there because the person is aware of it. And they're aware of it for whatever reason (one of which could be advertising, but who knows!).

The endgame for advertising is when people become blind to ads, either because they become used to them, or because they hate them so much they "ignore" them (or so they tell themselves). So in both those situations they completely block out the "ad" part of it, and "I saw an ad about a thing that..." becomes "Wasn't there a thing that...?").

[1]: Maybe even defensively, like "if we don't find anything better (or we're not in the mood for anything in particular) there's always this option as a last resort".