Seconded. Aside from it essentially amounting to art theft, and although some of the stuff out there could scarcely be called "art" others clearly have put in a serious amount of time, effort, and talent, it should not be possible for other groups/individuals to steal it in order to impersonate someone else.
There should be two categories: locked, and shared. Things like Alliance Emblems, Shop Logos, and other such symbols which are a personal representation/identification (a trademark, in essence) should not be something any Tom, Dick, or Harry can snip out of their history and claim as their own, and thus would go into the "locked" category. Meanwhile all the memes, emojis, or "reaction pics" can be in the "shared" file because their meant to be spread around.
It's one of the things keeping me from getting invested at all in learning how to do Symbol Art. I hate to think that I could put effort into making something just for someone else to snag it, claim it as their own, or worse yet use it to discredit or troll myself or others.