Why does it bother you that they are sending money that THEY EARNED thru their own Labor, back to Mexico
While not even blinking an eye at the hundreds of billions of dollars American corporations send overseas or keep in other countries? It's so called "free trade" for them?
I don't see them sending their own earned money to Mexico as a problem, because I think it probably keeps more Mexican people in an acceptable standard of living that makes them want to stay in Mexico, their own nation, instead of even more people from there, needing to come here to make enough to survive.
If Mexicans can have more money to spend over there in their economy, then a result would be more jobs being created there, and it would keep them there,and eventually this survival need for them to send a family member to the USA for earned income to send back home, would be diminished.
Canadians (for the most part) stay in 'freezing your ass off' Canada, because they have a thriving economy...