If nobody spends XBT to buy stuff or transfer value in some kind of transaction then you will all soon be hodling monopoly money. Its utility as a digital currency is what makes it valuable
Its utility as digital currency is not about being wasted on consumerist crap. It's for gentleman's transactions like moving money privately, cheating taxes, System D, and generally sticking it to the man. Not to say that there are things that you can't buy with a slavecard.