I gnaw on the grapes so slowly that it's not a big deal to pick out seeds as I go. But I'm not above eating some of them, either.
I just pick them off the stems, wash, let most of the water drip off and pop into freezer bags.
My mom grows Concord grapes and makes grape juice every year. Wish my lonely grape vine would do something other than just survive. Guess I don't have the right soil ph or right variety.