interjection, wages depend on the market conditions – both supply and demand. I personally saw years ago in midwest, a small group of very “observant” families hiring russian (Jewish) immigrants for way below minimal wage. Those ladies probably would not have any employment otherwise, but it still looked gross.
In your current case, first there is very low unemployment right now, and it may be that you live in a high-cost area, and it maybe that you live in an area with many people like you who are looking to hire someone, so demand is high.
Putting aside dina d’malchuso and current hot politics. What is the obligation here? On one hand, in classicil halocha, we prefer money to stay in Jewish hands, idolaters are not going to do anything good with it. So, when, say, two Jews are trying to get business from a poretz, you are forbidden to try to lure the customer away by lowering your prices. But, on the other hand, here we have poor people who came here to feed their families and to send money back to their relatives. Maybe we should pay them same, or almost same, you would pay a legal resident.