Absolutely. A vegetarian/vegan restaurant being able to advertise exclusively to those people is one great example. In that example you're a new customer, but

Absolutely. A vegetarian/vegan restaurant being able to advertise exclusively to those people is one great example. In that example you're a new customer, but you've shown interest in similar products so you're much more likely of a customer(and better spend of advertising) than advertising to somebody on a carnivore diet.