Big Macs and lattes will be purchased by cryptocurrencies sooner than you might think, according to venture capitalist and bitcoin fanatic Tim Draper.

"In five years, if you go to a Starbucks or McDonald's and try to buy a burger or coffee with fiat currency, the person at the counter is going to laugh at you," Draper told an audience Friday in San Francisco. "There's a real need for a currency that's global."

Draper's presentation at the Blockchain Connect Conference came by video and helped kick off a full day of panels and presentations from developers and investors. The event was so crowded that people were filling up the overflow room to listen on televisions, and Draper's video aired late because of technical difficulties.

Draper, who backed companies including Skype and Baidu in the earlier days of the internet, has made a personal fortune on bitcoin and has more recently turned his attention to initial coin offerings. He said in May that he was participating in the Tezos ICO, one of the biggest crypto offerings of the past year. That deal has been plagued by conflict, with the founders stuck in a financial battle with one of the leaders of the project.

Draper said there will be "fits and starts" in the emergence of blockchain but over time it will effect "industry after industry."