Bitcoin is valuable as a currency because of the economic efficiencies the bitcoin network is already creating as transactions flow over it. As with the Internet, more applications will flourish which will make the bitcoin network, and thus bitcoin as a currency, valuable.

At GDAX, we want to see new protocols and their tokens flourish.

Sales conducted on-chain through smart contracts couldn't really be done before Ethereum, which is why they are a newer concept. I think this style will become the most common over time.

Fred Ehrsam Quotes