Topps is just like the rest of the retail world. There was Christmas items in our grocery store and hardware store right after Halloween. I didn't check, but I'm assuming our Target/Wal-Mart were doing the same thing.
There's a little bit of me that thinks Topps gets this set out around Halloween because if it hits (re: bat down Acuna), they can control the product placement (or displacement) and have themselves a little hobby buzz in a time that's winding down product from an already oversaturated base design product. Just my two cents. If the Alonso or Vlad Jr, etc. takes off, then there's a new money grab and all of a sudden product isn't at WalMart or Target anymore and now appears on Blowout Buzz and Steel City Cards instead for 2-3x the MSRP.