Terry Benedict is a jerk, yes, and so is Willie Bank, Al Pacino's character in the 3rd one, but these movies aren't set in the Wild West, they're set in the modern era. The fortunes that are stolen are insured. This is explicitly stated both in Ocean's 12 and Ocean's 8. In the latter note that it's James Corden's insurance inspector character who actually cares about solving the crime, not the jewelry company, because only the insurance company is actually losing any money and in some sense the jewelers are benefitting by turning a necklace that they can't actually let anyone wear into a giant pile of cash they can actually spend. That's why he initially suspects fraud, not theft.
See, in the aftermath of Ocean's 11, Terry Benedict's insurance company backs up a Brink's truck and deposits back into his vault an amount of money equal to what was taken - 160 million or whatever it was. That is a massive loss to that company and they'll have to raise premiums not only for Mr. Benedict, but also for literally everyone they insure, which means expenses all across the casino business and beyond just ticked up a little bit, and all of that gets passed onto the consumer.
This is the part the films gloss over. They make it look like the one who pays the price for the crimes in question are horrible casino bosses with dubious ethical histories, but in fact those people pay relatively little price. By the end of Ocean's 13, Terry Benedict has had the initial amount that was stolen from him doubled, crushed a major rival, and gotten a massive payday which even though it was donated to charity benefits him anyway. The only thing he actually lost was Tess, which doesn't actually seem to be something he really values.
Heist movies love to try and portray the crimes inherently being involved as only hurting bad people, and sometimes this is more or less true. Stealing giant piles of cash from a druglord, like in Fast Five or Triple Frontier, holds up pretty good, because that money has already been removed from the conventional economy (which is why money laundering is necessary to put it back in), but so long as you take money out of the economy by hitting a business that operates within it, then you end up hurting actual people.