Beast Tribe Crafts - Don't forget that some people still don't have access to HW content, or can't even afford it at the moment, so they're limited to everything pre 3.0. Why you'd think they're 'a waste of space' is beyond me? They'd have to re-do all of the Ixal quest stuff. And part of me is wondering if you're just saying this just because you have full 60's in crafting (Not everyone does)

Allagan Peices/Clear Demimateria - They're used on the MB to let players basically take more than the 1.2m gil limit when they server transfer. Sure you can put another 100k per retainer, but for a lot of players, that's not even a decent bit of what they have. Not to mention the players who server jump because their friends are on another server (Like what used to happen when character creation restrictions in 2.X content)

Weapon parts - You mean the stuff to make the 'Original Relic'? Again, some people can't get to 3.0+ content, why the hell should SE remove them and block people off from ever doing the first relic quest?