Rack Cover

Why do my Harper's Bazaar issues have different covers than the ones I see in stores?
Whenever I see the same HB issue I received in the mail on a magazine rack, the cover is always different than mine (my cover always looks like it's part of the photo shoot inside the mag, as opposed to being a facial shot). Is this because subscribers get a "special"(?) cover, or what?
Because if your a subscriber your counted as special customers, the madonna elle subscription cover got sold on ebay for £80 you could do that in the future with yours
U2 CRAZY TONIGHT EDGE RACK RIG COVER
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