I had always assumed that "Maxwell House" referred to "House" in the "household" sense of the word rather than "physical building".

Apparently, though, it refers to a large hotel that was named "house" from the get-go.

https://en.wikipedia.org/wiki/Maxwell_House_Hotel

The Maxwell House Hotel was a major hotel in downtown Nashville. Because of its stature, seven US Presidents and other prominent guests stayed there over the years. It was built by Colonel John Overton Jr. and named for his wife, Harriet (Maxwell) Overton. The architect was Isaiah Rogers.[1]