As a workaround I did connect my Pixel phone to hotel wifi and offered hotspot to which I connected the Roku. But that means Roku streaming goes twice through wifi in my room and all through my phone, which I have to charge. A workaround, but a kludge if I ever saw one, to be sure.
I doubt you were using the hotel WiFi once you enabled your hotspot. Unless your phone can do both at the same time (which I highly doubt) all you did was connect your Roku to your phone and then used your phone data for the Roku. I will say I've done that myself with an Android player I have that I am experimenting with for travel.
I do know what I am doing. You, atc98092, can doubt me, but that doesn't change the matter: I am using both the hotel wifi _and_ offering hotspot to Roku, because my Pixel phone on Google Fi _can_ and _does_ both at the same time. I realize not all phones may be capable of this, or some providers may preclude this functionality, but I'm lucky to have found a combination of hardware and provider that enable this. How do I know I'm achieving this feat? I have my mobile data turned off. And am regularly checking my mobile data usage. After an entire evening of streaming my total mobile data usage for the current billing period (cycle ends in 8 days) is still 0 bytes.
However, let's not lose focus: whatever kludgy workaround I ended up using, it is Roku device that should connect direct to hotel wifi.
Oh, I'm not doubting you. It is absolutely dependent on the device. I tried on my iPhone yesterday activating the hotspot while connected to WiFi, and it WiFi connection indicator immediately went away on the home screen. It's good to know that it works with a Pixel phone.
