I understand the OP's concerns; certain hats have been replicated fairly extensively. For certain ones I agree(clown noses, for example, should include a wig or something should they be done again). However certain designs(animal ears, for one) are released almost every year. There isn't anything wrong with that; if anything it lets everyone have a personal crack at the design, and players will choose if they feel it's better/different enough to buy.

Imagine telling all the new players "sucks to be you, cat ears are out of the shop and will never be released again". they're like snapback hats or any other style of cap... They will look similar, there isn't much variation possible there outside of coloration(and whatever logo or letter you add to it).

Wolves are a great theme, I've got two wolf hats and they're very different and are an example of how easy it is to fit multiple hats into different things(the one from fairy tale nexus, which could be my favorite hat ever made, and the one from club crypt).

Overall; certain hats will be remade every year(animal ears, caps, headbands) whereas other hats originality should be fairly simple to maintain. Asking staff to "stop using used designs" is illogical and impossible. However stylistic differences being maintained is should be something staff should be held accountable for.