ebay is the only one of the 3 you listed where the seller HAS the ticket... stubhub and ticketsnow both just subscribe to eventinventory, a secret "skulls & bones" society... if you dont believe me, check out the inventory on stubhub (which i will admit, has eventinventory, plus others), seacoast, ticketsnow, acetickets, tickettown, and ANYONE you know... it is very obvious, since some of the text notes will be the same.. in fact, you can just change the number in the URI, and when you find the lowest price on the seat you want, that is the real holder of the ticket... each member of eventinventory can advertise a ticket they dont own (usually someone like vivid seats in chicago owns them), and they can set their own markup... the lister doesnt care if they sell them or not, since they dont own the hotpotato... if they sell it, great, if not, it costs nothing.... thats why, on the night before a game, you see scalpers like vivid dumping seats on ebay... the dude in chicago doesnt want the hotpotato.
if mike reiss would like the full story, i would be happy to give a confidential interview to him... only to reiss... and only to help the patriots fans.