At the risk of angering some people, I will say that I do not think it is rude to get a table when waiting for food.
We used to not look for a table until after we had the food - and too many times, could NOT find one even close to the venue.
I am not going to pay what is sometimes a handsome amount of money for the counter-service food, get the food, and then not be able to sit down and enjoy it before it is cold. Neither will I agree to think it is reasonable to have to stand up and eat it while dodging crowds of people walking around the park...
Sorry - we will always look for a table first now...