I'm not sure about counter service, but we ate dinner at the Liberty Tree Tavern the night of the PPP. They alerted us when the parade was coming & asked my princess if she wanted to watch it from the front porch. So, we watched from the porch & then returned to the table for dessert.
No they were not. Cosmic Rays and Pecos Bill were open. Neither a big favorite for us so we go before the party if we can (you can get in at 4 pm with your party ticket) and eat at one of the others while still open. Then a snack later in the night. Maybe Casey's was open or smaller venues, but we don't usually eat at those. .