The fact that you want/can pay $5/mo probably means FB earns a lot more than the avg on you.
Advertisers pay more to reach people with higher disposable incomes.
I offered to pay 3x the average rate to account for some of that. I think that moves me into covering the average spread across the US and Western Europe (about a third of their active users). Now, I'm still probably one of the more valuable people, but it would be the average cost if all the revenue was spread across people who could afford that cost.
Facebook already claims they don't use a profile to market to me. (It took some digging, but you can delete your tracking profile conclusions and turn off a lot of things.) Which means (assuming they're honest), I'm probably not a high value user because they can't target me for high value ads. This would just be giving them an alternative revenue stream to compensate for that. (So a strict improvement for Facebook.)
...Can I just give FB $5/mo to not keep their creepy profile on me? They get more money, I get not as creepily tracked.