Chances are, those 'other sites' will be over populated with commercial advertising from bizarre and often un-related people, or will sell details on to list farmers.
Yes, we do have adverts in the side panel, and in the header on the main page, but they're pretty unobtrusive and we know for a fact that they are well vetted......one of them was replaced by an 'anti' equivalent in fact, when that particular company shafted the boss
The fact is, a big active site has significant costs.
This one survives through a subscription system, and most people who subscribe do so year after year, having found it's well worth it
If you don't want to, then don't......simple really