its only fun project which its creator and even dev team never think doge will survive and even have current price. but now doge used to reduce transaction fee and alot traders convert their coins to doge while sending to another wallet
If it's only for reasons of cheap transaction fees at the moment, I don't think Dogecoin is the only one that has this, but there are also several others such as Matic and some even free ones like BUSD if the transaction is considered with others or internally in the network.
So for now, it's not only Dogecoin that has cheap transaction fees.