Detruire: I'm currently with Slingshot who provide me with a static (well, close enough: I've only had it change three times in almost five years) IP address
at no additional cost on their unlimited NDSL plan. This suits me just fine, and I'm certain that most other people would be happy enough with such a setup.
With Bigpipe, however, you need the static IP option if you don't want to be dumped into a CGNAT pool,
No, we offer 'sticky' public IP addresses (like you have with slingshot) at no charge, people just need to ask.
Static IP is not the same thing though.
Slingshot charge $10/month for a static IP
which I'm sure is why most people requesting static IPs are doing so.
I hope not, because they can have a public IP at no charge if they want.
If I am correct, you can't accurately compare your proposed pricing against what other ISPs are charging for their "static IP" option. Instead, you should be referencing what they charge for their "no CGNAT" option.