Sometimes I'll get a notification that someone watched me or favorited a pic. I go to check their page to thank them or whatnot, only to find that they have no favorites in their gallery or no watched people.

What's this about? Are they trying to give a compliment, but want to keep their page uncluttered? It isn't mega common, but happens enough that I cock my head a bit in confusion.

It's not offensive, just confusing. I hope someone can shed some light on it for me.