kotaku has a big article up basically asking 'whyyyy are collector's editions not coming with the game anymore' and like. Answers:
- You don't have to evenly split your stock of collectors editions among every single console/platform the game is on and end up with overstock of the least popular one. This split is even larger now that modern consoles have no-disc-drive versions as well (and it means there's more available for ppl who DO want them on popular platforms)
- The game and the rest of the CE are usually manufactured by different companies and not forcing an extra step of coordination between them reduces costs, shipping and manufacturing time
- You can sell extra copies to people who already own the game later much more easily
