That's possibly because Cronos claims a lower market cap than others and could be perceived as a more attractive bargain by investors.
Interesting article about why Cronos might have jumped in price today. I own a few shares in Cronos so I was glad to see it. I still say the long term looks bright for the stock, although I wouldn't buy anymore at these prices, after the big run up.....
Read the full story here...
https://www.fool.com/investing/2019/01/28/why-cronos-group-shares-soared-today.aspx