It’s to do with cost - Microsoft will transfer ”additional data” at no cost while Sony want to charge for it. You only get new costumes if you ”actually buy” them.
This means you can see a player that has bought the alternate costume DLC but you haven’t on Xbox 360, but on the PS3 version they’d be wearing something vanilla. ”The DLC for the newest costumes is additional data that must be put on your machines from the first-party networks (XBL and PSN),” said Capcom’s Seth Killian.
”When you add new data to an existing product, there are significant costs to do so charged by the first parties. On XBL, those costs were covered by Microsoft. As a result, the data is distributed to everyone, so even if you have not bought the new costumes, you can still see them if you’re fighting against someone that has because you still received the new data required to display them.” Of course Microsoft charge for online features.
”For Sony, those significant costs are not covered. As a result, you only get the new costume data when you actually buy the costumes. Those that don’t buy the costumes can’t see them, because the new costume data isn’t present on your machine, and so you only see costumes you already have the data to represent,” continued Killian.
”The story is a bit more complicated because the costs of adding new data vary by region in some cases, and some additions are free, or free within a certain timeframe, etc., but the bottom line in this particular case is that Sony would have charged Capcom significant fees for distributing the new costume data to users that hadn’t actually bought the DLC. Microsoft covered those costs, so the costume data is visible to all there.”
Now you have your explanation. ”I wish it were the same all around, but hope this info helps,” he added. There’s not much boasting your DLC buying prowess on PS3 then.