I so often see comments on posted photographs that include the phrase, "thanks for sharing". Since when does sharing an image one is happy to have made and is proud of qualify as narcissistic? As any photograph posted on this site is open to critique whether appropriate or not given the forum, the posting photographer is vulnerable to highly negative assessments as well as high praise or, maybe worse, being totally ignored.
I think any self respecting narcissist* will utterly avoid apug in favor of a site on which their work is not vulnerable to any critique at all.
*no doubt a redundant descriptor. lol!