If they don’t fight that use case, I suspect they become a lightning rod for stolen credit card transactions.

It's bad for the rest of us customers. a) more effort goes into fraud, more risk of annoying false positives, b) easy to max out resource utilization which shortens hardware lifespan, c) boom and bust industry makes planning harder which means they can't run on as predictably low margins. This all increases costs and makes free tiers harder to offer. Miners are an easy group to say no to because they don't overlap much with the rest of the software business world, so the reputation hit is small.

$20 says 100% of crypto mining in cloud = your customer got p0wned

Oh, thats an easy $20.

I mined Ethereum in azure during the height of the crypto boom, and looking at my statistics of vms i was able to get i am pretty sure some other people did to.

On 5k$ spend on azure i got round about 7k$ in Etherum when sold the next day, this includes german Sales tax and some loses i made starting out when not accounting for the german sales tax early on.

I think the whole timeline where this worked was about one and a half weeks(Germany, if you played around with exchange rates and sales tax potentially a bit longer), but it worked pretty well.

Azure was also perfectly fine with me doing it.

Yeah, and once that brief period of easy arbitrage was over, 100% of all people who are paying $10 to mine $1 worth of crypto are people who are trying to steal the $10.