Several reasons why you're wrong.
It's harder to find people that are already here.
The ones that are working are less likely to be on welfare.
The ones that are working are less likely to be criminals.
Punishing citizens won't de-incentivize future illegal immigration.
Every year we postpone this is another year of the problem continuing unchecked.
Stopping the problem at the source is always more efficient.
Jobs are not the only reason people come here illegally.
I have given you the power to not be retarded. Whether or not you choose to accept it is up to you.