Actually i wonder it too. Not just paypie, most of the icos using erc20. Has Erc223 has some diffuculty we don't know?
I would love to hear a dev, why they are choosing erc20 instead of erc223
Because of the many issues from explorers to exchanges.
Right now, now exchange supports ERC23 coins.
There's one coin named "Senderon" it's ERC23 but dev is having difficulty listing it on exchanges as they are not yet ready to upgrade.
Yep, forgot about the fact that it's really easy for exchanges to list ERC20 tokens.
And by the way, ETC is supported by a lot of whales which hope to push it at 100$ at the end of the year.
But there's no reason for such a pump, Ethereum is now widely adopted and used. Just watch the money put in ENS Domains