My gut feel is that what you are proposing it OTT. It would be something of a PITA to move the stock in and out of the store every day, not to mention the potential for damaging it. Many airgun stores have display cabinets in the customer area of the shop with trigger guard chains or cabinet alarms (even shotgun and S1 shops).
It doesn't really matter what anyone on here thinks, the FEO is the one to make the decision and I would strongly suggest that you consult with him - they are usually helpful and pragmatic and he will have a good feel for the risks specific to your particular situation.