Comcast does exactly that in the US.  Some people turn it off though.  I can't recall if just the guest hotspot can be disabled on it's own or you have to just turn off wireless completely and use your own kit.

Probably depends on the provided gear.

Slightly off topic, but the cellular providers here also sell femtocells to customers that want better cellular service in their home or office.  They basically offload (and charge) their customers to expand the coverage over the customer's own internet service.

Brandon Svec 
15106862204 voice|sms
teamonesolutions.com 

On Fri, Nov 20, 2020 at 3:28 PM Rod Beck <rod.beck@unitedcablecompany.com> wrote:

Hey Gang,

How do the cable companies generally deliver this service? A friend insists it piggybacks off the WIFI radios of existing cable company subscribers. In other words, the cable company WIFI router in a flat is providing both a private link for the flat's subscriber, but also a public hotspot service.

I concede it is possible, but I am skeptical that the high quality of hotspot service we get here in Budapest could be achieved that way.

Roderick Beck
VP of Business Development
United Cable Company

www.unitedcablecompany.com

New York City & Budapest

rod.beck@unitedcablecompany.com

Budapest: 36-70-605-5144

NJ: 908-452-8183