Back in the day when me and my friends worked at the various stores, we’d leave carts in the far reaches of the respective parking lots. Gave plausible deniability to fucking off 10-20 minutes, then you could combo chain that with a bathroom break, doing “go-backs”, or just walking around with a random item you were “bringing to a customer”. Or helping an old/short person with their shopping (customer service comes first ;) ).
Anyway fuck grocery bagging and cart pushing- And just generally making teens do mindless busy work for small business tyrants. Give them agency in work or let them be free; anything else adds literally no value.

you definitely should always return it. You are scum if you don't.
death to shopping cart returns.