about this:
TwiceDice uses the gaming token Dagchip (DCP) to participate in all casino games and betting. You can buy DCP with a wide variety of payment or currency options. There are no conversion fees when depositing or withdrawing Dagchip.

here:
https://coinmarketcap.comI didn't see anything about this altcoin, wouldn't it be easier and more practical to just accept bitcoin and some faster altcoins with a low fee?
I'm sure DCP (Dagchip) is not an altcoin, it is just a chip to play their games.
Just like when gamblers go to land based casino (especially poker games) they will need to convert their fiat money into chips so they can play on the poker table with that chips.
Once gamblers finish their session, they can convert the chips back into fiat money in the cashier.
Here in this site, once you make deposit then your deposited money will be converted into dagchip and if you are going to withdraw, this dagchip will be converted into real money based on what currency you want to withdraw it.
Actually it is similar to the one you can find in come casinos such as duelbits and rollbit, where your deposited money is converted into "coin" where 1 coin worth $1.