It hasn't been transferred to the employee, but it was (unless the employee is an idiot) a factor in the negotiations. The employee was paid less in order to cover the cost - and both sides know it.
In negotiations over w-2/10-99 status, it is a rather significant factor.
How many people work over-the-table instead of under just to get that 7.5%?
I considered not quiting a job in which I was losing money in order to get that (and other) tax paid. If I were in a better financial position, I'd keep driving courier (my costs per IRS milage allowances are higher than my pay) as a tax loss.
This is sort of an FOB situation, rather like the question of who's money the bank robber stole if cash from/to your account was on the counter when he pulled the gun.