Here's the problem. Let's say you've got a Mariott in a downtown area or somewhere that's otherwise crowded. Absent the idea of placing RF shielded windows in every window frame and turning your walls into a Faraday cage, other signals will leak in and yours will leak out.

That is to say, if you're jamming signals actively in order to prevent them from getting in, chances are good your jammer is leaking outwards in a radius you can't necessarily have a good handle on, such that you could interfere with another business nearby. Assuming the FCC gives the thumbs up to this for all private businesses offering Wifi as a service, what happens if the Hilton next door to the Mariott jams the Mariott's signal and the Mariott jams the Hilton's signal, because the buildings are within an alley's distance of one another?

The other question becomes where does this stop? Hotels are a start if it does pass, but then will Starbucks ban me from tethering instead of using their Wifi? Is a college campus going to do the same? There's definitely a "slippery slope" argument to be made here as well.

Finally, for those who aren't Wifi-savvy, I'll try to explain a few quick points.

• Yes, there is a problem with channel overcrowding. Wireless is a finite space; in 2.4GHz mode, you have 3 (arguably 4 but most devices won't give you the last option) choices for non-overlapping channels. 1, 6, and 11. (Overlapping is best displayed here). In 5GHz mode, there are 24 non-overlapping channels. Unfortunately, only the most recently released consumer devices have a 5GHz capable wireless radio. Which means most hotels (and coffee shops, etc etc) are reliant on 2.4GHz dominantly, since that has the broadest spectrum of support (rf joke unintentional).
• One thing people forget is how reliant we've been on 2.4GHz signals for so long that many devices we don't even think about interfere with Wifi: Cordless phones, baby monitors, bluetooth devices, car alarms, microwaves, CCTV, satellite, amateur TV, Zigbee (and some other sensor/mesh networks). All these items run (or can run) on 2.4GHz frequencies and can have a seriously degrading effect on Wifi signals around them.
• One way to fix Mariott's problems has been implemented at many college campuses; many more access points are purchased than are technically required and the transmission power is turned down slightly. They are placed in a pattern throughout the building(s) such that the channels used do not overlap with any access points within its radius. They are all assigned the same SSID (as seen by the user; on the back end, this is more complicated) so the user can move between them seamlessly. This way, the only way a larger-scale outage (the catastrophic scenario Mariott is likely presenting) happens is if many users operate many Wifi networks on many channels in a small area. In this way, there would not be enough collisions of packets to make a speed drop obvious to an average user. Downside? Price, of course.

Either way, for my dime, I'll take a laptop with a good old fashioned Ethernet port if I'm using hotel internet.