Stupid question about going to 2 supermarkets in a row

I want to go grocery shopping to Lidl and then Biedronka. In my country if you enter a supermarket with other supermarket's shopping you are supposed to leave the first bags inside a locker, but I haven't seen any in my local Lidl or Biedronka. Can I enter Biedronka with Lidl shopping in my backpack?