We are a delivery company that focuses on bikes. We tell the rider to check with the store if they can also take their bicycle inside. We recommend them to lock it outside, but if it's possible they will usually take it inside.
As the store owner you can decide this yourself. We understand that the store probably has several policies that may conflict with this, so we do not dictate this for the stores. We advise you to take a clear standpoint in this situation and tell the riders from the start that you allow them to take their bike inside or not.
We ask this because we have some partners that allow the bicycle to go inside, so maybe a rider can get used to it. Tell them when they are not allowed to do so.
The rider doesn't want to listen to your advice of leaving it outside? Contact support, and we will make sure that this is handled correctly.