Ironically their customers trust them because just like other businesses around the world, the customers rely on the jurisdictions of where the exchanges are incorporated to uphold the law and make sure the exchanges don't rob them. The same jurisdictions many crypto-diehards think need to disappear...

Would you trust an exchange name "Uncle Vlad's Russki Crypto Exchange"? Probably not, right? Because if they take your money, and you call the Russian version of the FBI, they'll just laugh at you. So you think your money is safer in a crypto exchange where the founders would be arrested if they blatantly stole your money...

This is the main thing that has always seemed odd to my about much of enthusiasm for crypto.

People seem to conflate "it works like physical cash but it's electronic" with "no banks no laws no regulation" when its very obvious that banks and governance are still necessary.