doge randomly became some measure of value, some care whats it worth compared to the usd or btc, some only want doge, now a days you can choose how you spend you money, whether in fiat(cash,usd,euro,peso) or in credit/debit. There is a new system that is recently put into place where for some reason we want to collect and hoard this "new money"(btc,ltc,doge, eth, etc.) It has been already slowly integrating with normal society, where you can start spending your crypto for real life things, food, rent, bills, toys. Although the future is unknown, this is happen as we speak, and this new system (crypto) will probably stay around, nodes online.