Just a thought/theory in addition to those already mentioned about spiders and creapycrawlies,  but the top bit on my page at the moment states 6930 online, however if you view the members online list it said 620 (no I didn't count them, I copy pasted the list to excell )

The main word to consider is ONLINE and not viewing the site, if you leave yourself logged into renderosity (ticking the 'stay logged in' bit and using enabled cookies) this may still get recorded.  The people with rendo pages open are probably 620 and those looking at other sites but still logged in from a day/week ago is probably 6930.

 

Tools:- Win10, Dell XPS8900, ZBrush, Marvelous Designer 11, Hex 2, PSP8. PSP 2019 Ultimate, DAZ Studio, Affinity Photo, Affinity Designer, Filterforge 11, flowscape,  Classic UVMapper, and several headache tablets.