This is the highest joke of the century, you not telling the owner of a business the risk involved in bitcoin payment is a big turn-off, and I advise you to take time to educate the director about everything regarding bitcoin because leaving the director in the dark may not go well if things go side way and there is a need to wait for something, and as a business that offers retails services such as supermarket, there will not have plans to hold Bitcoin for the long term, but to hold as a currency for exchange and daily payments.
So it os advisable you teach the director everything he needs to know both advantages and the disadvantages.