I can understand past seasonal items to an extent. Though I'd rather have them purchasable ingame like the past practice in ARR.

This is a MMO and not a regular single player or multiplayer game. Items have more value behind them here. The example of other games having preorder items as DLC is a poor one. Those games don't have the longevity like MMOs do.

Bonus Items shouldn't be in a Cash Shop, my opinion. Legacy items since sadly mentioned, should never even be considered, period.