>>942035093
Illegals pay federal income tax.
If the employer pays them, they would almost certainly avoid regulatory scrutiny by normally deducting from their income like they would any other employee. The IRS doesn't care if you're a citizen when you're paying. You could work for cash and your employer could use your passport to file for an ITIN, and deduct your taxes that way, never giving you a social security number, and never involving you. The IRS doesn't care if you're actively committing a crime, they want their money, and do not care who it comes from. You do not need a social security number to pay federal taxes.
It's a given they pay every other type of state tax, like tolls, excise tax, road taxes because in many places because registration is tied to your vehicle and temporary driving permit.
Tl;Dr the system already thought of all of the right wing conspiracy theories that are currently being used to justify laws that'll be used to attack normal Americans.