By telling their access points to send deauth requests to all devices that aren't on their networks.
And yup, 802.11 tells devices to deauth even when receiving unencrypted deauth requests from access points the device expects to be encrypted.
And yup, 802.11 tells devices to deauth even when receiving unencrypted deauth requests from access points the device expects to be encrypted.
One is to make a network that's so good people will pay to use it.
The other is to make a network that's average, but intentionally make other networks worse, so that people will pay to use yours.
Since you're reading HN, I imagine your strategy is the first. Hence, you don't see the need to interfere with other users of the spectrum.
Wifi clients are notoriously awful at roaming. You would think they would prefer the strongest signal, but they seem to select randomly, no doubt depending on driver/firmware versions and bugs. If you've ever used an enterprise WiFi network where roaming works, it's because the APs talk to each other, make a selection as to which AP is best for you to talk to, and then deauth you from the APs that you shouldn't be talking to. So deauths are actually essential to making Wifi work well. The problem in this case is that Marriott is going above and beyond industry best practices and is just trying to kill _everyone_'s Wifi, presumably for their own financial gain. That's a violation of FCC rules, so they're trying to have the rules changed.
Meanwhile, I can just operate my network under Part 97 instead of Part 15 and it would still be illegal for them to intentionally or unintentionally interfere. Though Part 97 Wifi is a bit of a grey area.