RPGMemes

Ah. I see you're unfamiliar with the tale of Old Man Henderson. Enjoy.

(To be fair it was specifically the lack of garden gnomes that was a significant plot point in said tale, but characters in a setting being aware of a lack of garden gnomes sort of implies that garden gnomes do exist in said setting... but, again, given Old Man Henderson's nature they could have easily just ever have existed in his head...)