It has to do with your credit score, some employers think that if you have a low credit score, you are more likely to steal from them, and high credit card debt will lower your credit score.

I worked in the HR Department in a Company, and they checked the credit scores of their employees yearly, and if a particular employee’s credit score dropped below a certain number, their name was put on the next layoff list. It didn’t matter how well their job performance was.
However, the employee was never told the reason for their layoff.