Think of who is in the 1% of a country's wealth--a mix of capitalists who were good at acquiring that currency and folks who inherited it. In the cryptocurrency world, the moneyed are the creators, the miners and in the case of dogecoin, the creative-meme class who serve as a marketing arm. Many of them are in it for the lulz, and consequently have great upside with little downside, since it will always retain an intrinsic value as a karma proxy. The speculators may inadvertently make real-world millionaires out of this class.
It would not surprise me at all in the next year to see companies with large social subcultures at least attempt to launch their own cryptocurrencies, or extend their in-game currencies to become linked to a cryptocurrency.
Emergent decentralized currencies address both – and might also improve centralized-proprietor currencies by competition and precedent. (Proprietors will accept more community input, and win greater tolerance from governments, because of pressure from alternatives.)
The thing to watch for: when another online community embraces the dogecoin tipbot culture. That would be a strong indicator of long-term stickiness. The OP joked about having no /u/dogetipbot on HackerNews, but that's exactly the kind of feature that I suspect will start turning up in a number of communities.
With regard to games, Valve hired an economist some time ago. I'd love to see if they have anything planned with regard to innovating in this space. Could you have an in-game currency backed by a cryptocurrency?
I think the point is that people do not buy Dogecoin because it's fun in itself but because it's the currency of fun, in other terms, their currency. "Their" meaning "a slice of the population" as a country is a slice of the population too. "Before", currencies were determined by geopolitic, now it's up to the people proximity in the wider sense. It's not happened yet but that's what the success of Dogecoin suggest.