It seems like ad-blockers have had a huge negative impact on SMC. Yet, in some of the other forums/sites I visit, I notice prominent ad placement that isn't filtered by my ad-blocker (one example). Other sites (including Canadian Woodworking), have a pop-up that requires you to disable your ad-blocker before visiting. Are those not realistic options for restoring the lost ad revenue? (I genuinely have no idea)

I read several FIRE (Financial Independence / Retire Early) blogs/forums that are fairly transparent about their ability to produce 5- or 6-figures of advertising revenue per year. As Lee alluded to, the $6/member fee seems like it would be peanuts compared to that.