The Bank of America payroll system we used was automatically withholding the payroll taxes from all of our paychecks every two weeks. It then just left that money in our company's bank account instead of sending it to the government because I never discovered the "submit tax" button.

I suspect that it was deducted from their pay but didn't end up getting sent to the IRS.

Employees probably paid their half automatically, but the other half is on the employers' books.

The employer's half is what is commonly referred to as "payroll tax."