Hello SurfnTurf! The issue is that Coinbase is designed for retail investors, convenience and ease of use. Coinbase holds the private keys of the tokens on their site rather than the investor. As Coinbase is currently set up investors may not receive ERC-20 tokens that are issued in ICOs.

In fact many ICOs will have a strong disclaimer not to send in funds for an ICO from Coinbase otherwise there is risk of capital loss. As a best practice professional investors should control the private keys of their ETH and BTC holdings. Ownership of the private keys gives an investor maximum flexibility in the event of blockchain forks or other events which may affect the value of the crypto currency.

For Ethereum, I can recommend the www.myetherwallet.com wallet if an investor wishes to transact in ICOs. Promoters of ICOs are well aware of Coinbase's limitations and for this reason will shy away from using Coinbase in their ICOs either for distribution or receipt of funds.