not just the US, I've experienced this outside. "Upscale" hotels and resorts do it mostly. Cheap and business-travel oriented places have free internet.
Something is fucked up about Motel 6 and Hampton Inn having free WiFi, but not the Grand-god-damn-Hyatt, Omni, etc.
I've been in quite a lot of hotels last year in Europe and I didn't have to pay for free Wifi... the only places where I still see this happening is in the states.
and yeah, totally fucked up..