When I get home I can check my complete list of stays and contribute more, but offhand:

no-weekend:
San Antonio Marriott Rivercenter
San Antonio Marriott Riverwalk
Crystal Gateway Marriott (Arlington, VA)
Crystal City Marriott at Reagan National Airport (Arlington, VA)
San Diego Marriott Mission Valley (usually no prob, at least for me, getting bkfst on weekend in restaurant)
Boston Marriott Burlington
Washington Marriott
BWI Airport Marriott
Key Bridge Marriott (Arlington, VA)
Austin Marriott at the Capitol (usually no prob, at least for me, getting bkfst on weekend in restaurant)
Atlanta Marriott Marquis (concierge says lounge is "sometimes" open, and that breakfast buffet will be comped when it's not)

weekend:
JW Marriott Hotel Pennsylvania Avenue (Wash, DC)
Renaissance Las Vegas Hotel [not when I was there]

[edit == fix typo on Gateway listing, fix (apparent) error in Renaissance Las Vegas, added a few entries]