It's now widely trade and accepted, with many pairs and a low price. It's ideal to move funds, so it does serve a purpose now.
Or at least, it did, as it's clearly being manipulated: check the price and notice how, despite the strong changes in BTC/USD prices, the DOGE/BTC has been extremely stable slightly above 1*10^-6 which is extremely abnormal, and indicates someone with deep pockets is keeping the psychological price (like BCH/BTC but for different reason: someone decided it would never go below 0.1!)
This means the DOGE pump is just starting, as it is an often used trick to create positive attention: it ensures a matching performance for BTC/USD and DOGE/USD which is what influenceable people need to see to believe in a pump (a coin growing faster than BTC in USD terms will be seen in the 2nd phase of the pump)