This is a very interesting topic for discussion. I think that small merchants at the initial stage can attract customers to themselves by the fact that, unlike other stores, they can pay in cryptocurrency. As is well known, additional concessions to the client often play a positive role in trading. In addition, the audience of cryptocurrency holders is constantly growing. First, it can be in the form of an experiment, and then as one of the methods of payment. If this experience becomes successful with small sellers, then at first other small sellers will begin to enter payment for cryptocurrencies, so as not to yield to competitors, then medium, and then large ones.
Allowing crytpocurrencies for payments can be helpful:
1) Only in some particular type of stores. For instance, in stores related to tech products it can be success as people there would be familiar with crypto and such payment options
2) In only those countries where crypto is legal. There are some countries where crypto is banned and thus such a payment option is of no use there.