Staff entering rooms?
 

I got an e-mail from GH Seattle welcoming me to their hotel and at the very bottom it says "We enter and physically check all rooms on a daily basis." I have stayed at GH Seattle and Olive 8 before never had this come up. Are other members getting this too at other Hyatts? What exactly are they doing?

I was told this has to happen since the Vegas shooter stocked up in his room with DND on.

I see this at various properties but I think it's more marketing ("we are not ignorant of the Vegas shooting and want you to know that") and less actual big brother enforcement (i.e., I would expect that if you have the DND on, housekeeping will leave a note on or under your door asking you to contact them to schedule housekeeping, and not that they'll forcibly enter... but I would expect that you would encounter trouble if you wanted no one to enter for more than one day).

As others have said, this is in response to the Vegas shooting in 2017 where the guy was holed up in his room for days, stockpiling weapons.
Other hotel chains have also responded in kind - Hilton and even Disney at the WDW resorts in Florida.

In many countries around the world luxury hotels x-ray bags upon entry, and in some cases even check your pockets as you step through a metal detector

As platbrownguy notes, this is a property-based decision, not a company-wide one. My most frequently visited hotel is a Hilton that is one of the few actually managed by Hilton. During my 3 to 4 night stays there, I put up the "Do Not Disturb" and leave it up the entire time. I'm not ever bothered.

Granted, I ask the Front Desk if this is okay when I check-in and I'm a repeated guest (20ish nights there each year). So, I may be getting special treatment. But, my educated guess is that the hotel isn't interested in entering the world of security theatre.

But, you are correct that the Walt Disney World Resorts have this dumb policy.

Actually I believe this IS a Hyatt corporate policy now. They have also removed "Do Not Disturb" signs and replaced them with "Room Occupied" signs in order to manage guest expectations. This is the same approach that Disney has utilized - not sure who copied who. Bottom line is that it IS official Hyatt corporate policy for them to enter every room every day. Whether this, in fact, occurs is a different story.

This also happened to me in Uzbekistan (HR Tashkent). Not just a CONUS thing it seems.

Is this even new? Once (~10 years ago) I was staying in Vegas (MGM Grand) with my gf. She was working for a couple of days from the room while I was downstairs gambling so we had the dnd sign out, so she could work without stopping for housekeeping. After the 2nd day security came by to make sure that "everything was ok". I was not there at the time but it did not sound like a big imposition.

Yeah I don't get the paranoia about this. They have every right to make sure you aren't doing something nefarious in their room. It's not like a hotel room BELONGS to you... it BELONGS to them, and you are simply renting it for a brief period. If you owned it, that would be different, but you don't. A similar concept exists with apartments in most states: the landlord always has the right (with some limitations on notice) to enter the apartment for really any reason, including to make sure you aren't trashing the place.