Actually, in this case it isn't a ploy.
For the past year, year and a half online retailers like BBTS, Cornerstore Comics, Alter Ego, Toy Anxiety, etc. have received limited stock from Sideshow. They used to offer pretty nice deals too, like $30-$45 a new preorder, then Sideshow stepped in with their distribution policies and put an end to that. I still remember when Sideshow offered Free Shipping.
So yeah, that isn't a marketing ploy. These other retailers are just limited in what stock they can receive and sell. As for Sideshow. I bet they'll probably start to sell out or have the wait listing status in July or August. That's my guess.