I think a lot of people aren't aware that they don't pay ISPs for wifi, they pay for internet service. The wifi is a value added item that is provided by the ISP for convenience.
It's kinda like if the water company came and handed you some pipe suitable for home plumbing when you got your service turned on. The toilets and faucets are yours (computers and mobile devices, in this analogy) and the piping in your home is also yours, they are just giving you something simple to help get the water from their point of demarcation to your fixtures. The extra piping is there to help, but if things are awkward in your house, or there is structural issues that interfere with the flow, then that is between you and your plumber, not you and the water company.
Personally, I wouldn't want the water company to be responsible for my home plumbing, they have to make sure the water gets to my house reliably, and should be focusing on that.
To put it another way: wifi provided by an ISP is similar to the starter ink you get with a new printer, it's nice to be able to use it out of the box, but you're expected to either make it work for you, or replace it when it doesn't.