It is likely that these tokens were purchased with good discount. And to a man, such a difference is was large enough. Either there were other circumstances that we do not know. I hope that we will not see more such a dump.
Good discount 10 times? I very much doubt that there were such discounts. I'm more inclined to believe that Helbiz's helpless service missed a hacker who could get hundreds or thousands of airdrops.
There is no better discount for presale, in presale you get the token at lowest possible place, so I think it is good discount.