I've never said there wasn't any. Just that if you value a free tier (which you should if you want to attract developers) you find a way to deal with the fraud (or eat the cost). The fact that Salesforce either couldn't figure out (or didn't care to) the fraud and didn't want to pay for it spells bad news for the future of Heroku.
Again I don't think you understand the amount of resources that goes into anti-fraud teams in the hosting world. I used to work at a big hosting company and we had a team of 50+ people working around the clock to stop fraud ontop of tens of thousands of hours in engineering time to automate as much as possible. It STILL wasn't enough. I can only imagine how much worse it is when you have a free product offering.
They could've converted the entire free tier offering to a $2-5/month thing, which would still be very attractive for legitimate users. Fraud is a big problem, but it didn't mandate this specific solution.
