Investors are drunk on the Kool-Aid that is bitcoin, according to veteran market forecaster Peter Schiff, CEO of Euro Pacific Capital.

"No matter how high it goes, they're never going to sell," said Schiff told TheStreet.

Schiff also had some tough words for the cryptocurrency, which started 2017 at roughly $1,000. On Wednesday, bitcoin hovered near $15,900, down from its peak of almost $19,700. 

"Ultimately, I think bitcoin has really no value," said Peter Schiff, CEO of Euro Pacific Capital. "In the market, it has plenty of value. As long as there's buying, there's value. But when the buying goes away, so does the value."

Schiff said a lot of the paper profits will end up vanishing "when the music stops."

Meanwhile, TheStreet also asked Southwest Airlines (LUV) CEO Gary Kelly if consumers will ever be able to pay for an airline ticket with bitcoin.

"It's hard to envision, but it is astounding how fast [bitcoin] has moved and we'll just have to wait and see on that front," he said. "The way our monetary systems work today are pretty efficient."

We'll just have to wait!

Watch our entire interview with Southwest Airlines CEO Gary Kelly:

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