You're right; I was wrong. It makes complete sense for an advertiser to say, "Sell adds to people interested in X" and for i.e. Google to show those ads.
Even for less reputable companies, it seems you're right: it makes more sense to sell ads for a keyword rather than to make the advertisers sort through a mass of data. Is that the case?
Even for less reputable companies, it seems you're right: it makes more sense to sell ads for a keyword rather than to make the advertisers sort through a mass of data. Is that the case?