My observation of fast food places I have gone to in the past decade or so is that the language behind the counter at many of them is Spanish. A non-Spanish speaker would probably not be able to function. Fast food wages would likely go up if employers did not have a virtually unlimited illegal labor pool.
That is most certainly not true. You just happen to be in a market that has lots and lots of illegals I guess.
In my county, the distribution is 96% white, 1% black and 3% other (illegals). The illegals are off on construction and other labor jobs.
When you go through a drive thru here (or inside for that matter) you are more than likely going to be speaking to someone for whom English is their native language and can understand you. More importantly you can be reasonably sure they won’t spit in your burger, and that a lot of time, the food looks like the pictures on the menu.