If you build a store that accepts them they have more purpose than Bitcoin. A token with stable value is far easier to use as a medium of exchange than Bitcoins whose price fluctuates wildly and is non inflationary.
The small market value of tokens also make them easier to tailor fit into a micro ecosystem.
Has anyone coded transactions like this with erc20 tokens?
I agree, you need to have a coin for the store, which will not be affected by the volatility of the market, in the likeness of Tether. After all, the store can go bankrupt just one day after the start of the market fall. a very risky option and therefore strongly do not develop this topic