Christmas list shopping
Going from store to store looking for items to put on your Christmas list. To be contrasted with regular shopping as you're just making a list of stuff you want versus actually buying anything.
Store clerk: Can I help you find anything?
Customer: No thanks, I'm just going Christmas list shopping.
Store Clerk: Oh, ok.
Customer: No thanks, I'm just going Christmas list shopping.
Store Clerk: Oh, ok.