Lying about firing someone with cause is illegal. If you’re firing someone without cause, but claiming that it’s with cause so they can’t claim unemployment. Because the company’s unemployment insurance rates increase if too many of their former employees claim it. So the company has a vested interest in avoiding layoffs without cause, because it means their UI payments will skyrocket.
So lots of companies will fabricate a reason to fire someone with cause, rather than laying them off without cause. It’s blatantly illegal, but it’s up to the employee to prove. And many former employees won’t bother with the appeals process, because UI in many states is already notoriously difficult to claim to begin with. So the company is able to get away with it. When people complain about white collar crime going unpunished, this the kind of shit they’re referring to; Companies blatantly stealing from people, then not being prosecuted for it.