In this case, they were simply using a conference room at the Ritz-Carlton. Most of these folks have a house or condo in the DC region already.
But it would trigger me to ask who paid for the conference room? These aren’t free. Even if this were a smaller room...you’d be talking about several thousand dollars for the conference room, catering, coffee, etc. Somewhere in this spread...someone has a credit card and billed it to a foundation or think-tank. That might tell a fair amount of the whole story.
A group like this don’t go to a hotel incognito.