We've stayed at HR Seattle 3x this year and love it!
Hyatt Regency Breakfast is at Andare downstairs. You could choose the full buffet ($29) and order one item off the menu as well. We like their signature omelet!
The 8th floor lounge has snacks throughout the day (breakfast cereals to go, granola bars, chips, bananas, apples...etc.) soft drinks/bubbly, aquafina water bottles, and two coffee machines.