In the Studios, there is covered seating just in front of the Animal Actors theater. The closest food place is the seasonal pizza place in Kidzone which has been mostly closed, so you shouldn't be interfering with other diners.
At IOA, there are quiet areas all along the lagoon, where most people don't go. We've walked down there so infrequently that I can't remember how many benches there might be in the area. In Seuss Landing, the planters are raised, so you could probably grab a spot, but I think there might be additional options in the center area or Marvel Island, but unlike the area in the Studios these would be exposed to the sun. Otherwise there are outside tables at Thunder Falls in Jurassic Park and Circus McGurkus that I don't always see many diners as people opt to eat inside for the air conditioning, so if it's a not busy day those could work too.
