> some small company realizes they dont really use their cars that much so they rent them out again for 3 days a week to get some extra cash. is that fraud?

Most likely, yes.

There's a common fallacy that once you pay someone for a service, you are free to do whatever you want with that service. In the case of the rental car, the contract the company entered into would prohibit reselling the services and limit who can drive them and for what purposes.

Some people see these limitations and scream "Not fair! They paid money, they can do whatever they want!" The misunderstanding is that the price they paid was predicated on the specific use. They got a lower price for the rentals because the provider calculated the expected use case and priced it according to that.

If the small company starts renting out the cars to try to maximize how much they're used, that breaks the financial model. That's why this type of use is forbidden in every basic rental contract.

It's the same reason why you can't rent an apartment building and then turn it into an AirBnB. On a smaller scale, it's why you can't go to an all-you-can-eat buffet and load up on food to carry outside to your 5 hungry friends. This type of pricing is everywhere.

There is a vocal online minority who believe user license agreements shouldn't be enforced and individuals should never be considered accountable for following them, but that doesn't even apply to these resellers. This isn't a lowly individual user trying to get back $10 from their $20 per month plan that was going unused. There's no way to even achieve the scale and discounts without mass, automated fraud. They're doing chargeback fraud or using stolen credit cards.

It's not even a crime where the big corporation is the only victim. The higher the volume of fraud on the subscription accounts, the less real usage you and I get for our dollar. These people are jumping on the accounts targeted to individuals like us and abusing them to sell tokens to big corporations trying to abuse them at scale. People like you and I lose when these accounts get their limits reduced or the companies start introducing ID checks and KYC just to use basic services.