When my daughter graduated from HS, she was 17. She looked for jobs, she filled out applications at all the usual teenage job places. Nothing. I finally asked the manager at a Starbucks if they hired 17 year olds and she told me that she might hire 1, 16-17 year old, but that the paperwork and rules on hours worked were really prohibitive so they didn't like to take on more than one employee that young.
She finally got a job as a busgirl at a local retirement community, via a friend's recommendation. But it took her forever to try and find work and she was trying to save for college. This summer was worse, and she tells me that her friends at college (from all over the U.S.) were having a very hard time finding work.
I don't know if this is part of the illegal problem that you are experiencing; but it was very bad this year everyplace.
Personally, I am sick to death of the border problems, but the politicians of both parties seem unwilling to do anything about it.