Re: Providers pay too
Yes you pay your ISP for a connection, but usually the T&C forbid public hosting on a domestic connection.
And this should be made illegal with six or seven-figure fines per violation for ISPs to put these T&Cs. Internet connectivity is both ways, not a "grab stuff from outside" thing only. This is also why CGNAT should be explicitly made illegal as well.
Forbidding end users from hosting stuff or having a public IP is the equivalent of having a landline phone service that can't receive calls. Sure you can call, but it's pretty much useless as nobody can call you.
Interestingly, usage of NAT is one of the main reasons we have this "asymmetrical" data flow problem in the first place! Older IM programs and apps would directly peer between end-users, with the "central server" being used only for IP discovery; see how ICQ used to work in the early days. These days, thanks to NAT everyone has to go through a central server because NAT breaks connectivity everywhere and you can't be sure about anything on the other side anymore.