Do you need a Costco membership card to get food

Yes

You don't have to scan/slide your membership card to order from their restaurant (hot dogs, pizza, etc.). You do need to have a card to enter the facility under normal circumstances. If you get in without your card, you can get food there

Yes you need to have a membership card or a friend or family member who one.

If the food court is located at the front entrance you will not need a membership. If it is inside the club than you will need membership

Costcos with indoor food courts you need a membership

I believe to make any purchases there a membership is needed.