Walmart wouldn't run an ad in GQ highlighting it's clothing section: because the ad isn't going to resonate with the person seeing it.
However, unlike Walmart who would get on the phone with an account executive with Conde Nast (GQ's publisher) and talk through the campaign, most website advertisers and publishers do not have people dedicated to doing 1-1 sales. Publishers want the most money possible per ad unit and advertisers want the most sales possible within a reasonable acquisition cost. To balance those two things out and create value on both sides, ad exchanges and the demand platforms that tie into ad exchanges provide tons of targeting and remarketing opportunities. That allows advertisers to target their most profitable audiences. However, in order to offer all the rich and detailed targeting options, the exchanges and platforms have to know what individuals are doing so they can create personas and profiles of you.
If this happened magically in the magazine industry and magazine ads could be customized to the individual reader, then Walmart might buy some space in GQ if they learned a small portion of GQ readers are actually bargain hunters and shop at Walmart all the time for clothes and only read GQ more for their interviews and cocktail recipes rather than for men's fashion info.
However, unlike Walmart who would get on the phone with an account executive with Conde Nast (GQ's publisher) and talk through the campaign, most website advertisers and publishers do not have people dedicated to doing 1-1 sales. Publishers want the most money possible per ad unit and advertisers want the most sales possible within a reasonable acquisition cost. To balance those two things out and create value on both sides, ad exchanges and the demand platforms that tie into ad exchanges provide tons of targeting and remarketing opportunities. That allows advertisers to target their most profitable audiences. However, in order to offer all the rich and detailed targeting options, the exchanges and platforms have to know what individuals are doing so they can create personas and profiles of you.
If this happened magically in the magazine industry and magazine ads could be customized to the individual reader, then Walmart might buy some space in GQ if they learned a small portion of GQ readers are actually bargain hunters and shop at Walmart all the time for clothes and only read GQ more for their interviews and cocktail recipes rather than for men's fashion info.