Every hotel I've ever been in did not have a password to connect to the WiFi. The access point is open, but registration on a web page is required to actually get to the Internet. My guess is that this particular hotel has limited Internet access prior to registering, which is making the Roku think the hotel prompt in not required. Perhaps DNS access is open, or some other non-web protocol. I can't think of any way to trigger the hotel prompt under conditions like that.
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