This is largely a US issue.

My partner here in NL got fired from a regular retail job, but the company still had to pay her 3 months of salary because she had a permanent contract and worked there for 3 years. I mean it's minimum wage, but still. She also had a month of warning, plus she could choose whether she wanted to use her remaining vacation days or have it paid off alongside the 3 months (the holiday pay gets taxed up the ass though).