Yes they send it to many travel agencies. And Its not just sending, rather many agencies bid on that requests. As far as International air ticketing is concern, I rarely know that some one buy airticket from big giant like, Expedia, Travelocity, priceline etc. I am an international student here and all my student firends buy airticket from travel agents . And now many consolidators are marketing themselves as travel agents too and also they do have website where they sell tickets in retail.
