If you are facing this issue with currency value, don't you think that others will face the same problem? Will they be willing to buy Bitcoin and use it for payment in your mother's shop? Always think about your surroundings and try to think from their point of view. You will understand every situation more clearly. Also if the government is not supporting this kind of movement, it is better to stay away from it. Don't get involved with illegal activities which cal lead to major problems. Taking from my own experience. I am from a country where Bitcoin is banned. So if this is the same case there, better stay away from it.

The market is volatile and in order to keep the shop running, you will need more money in the future. What if the price falls and you are in need of emergency money? You will be in big trouble, not be able to sell those Bitcoin or sell at a loss. As I said, look at everything from another's perspective. If you think that everything is according to plan and you can carry out this, then go for it. But be sure to research and create a plan beforehand.