Hiya, I've moved this to a differnt forum, hope that's ok xx
Could you introduce paying for snack as a part of play - maybe issue or have a system to request and 'sign out a shopping token snack coin, from a role play customer service department maybe.
Low level book shelves as supermarket aisle
shelves
Print in the environment - logos from local independant and national supermarkets as signs / colour activities - maybe ask if they have any window posters for your role play / collage ?
Craft & mark making could be using card tubing and making own cans and paper labels ..
As an extention possibly use shopping as an overall theme for baskets / methods of transportation - wire - trolleys/baskets, wicker, fabric - bags, purses & wallets ...
Lotto game could be along 'which shop would you buy xx from ..
Guitar - music, wood - timber merchant, fruit - grocer, fabric -
haberdashery, Plant - garden centre ...
Keywords for communication - Frozen, fresh, produce, canned, chilled, dry, loose, packed, boxed, sealed, open ..
Hope this helps sounds like fun
xx