A lot of Mexicans, especially native Mexicans, are very when it comes to the people South of THEIR border. They are strongly of the opinion that Hondurans, Guatamalans and such are lower forms of life and there is lots of racial animosity towards them
Add to this the fact that the new waves of Central American illegals compete directly for Jobs and wages with the established Mexican illegals who have been in the US for many years and the only people who are welcoming the new wave of Central American illegals are the Democrat activists who are trying to flood America with illegal aliens
ABSOLUTELY spot on. They believe they are High Spanish (and a surprising amount of High German) at the core, and associate everything source of the border with lower Caribbean influence. And a lot of them are High Spanish, frankly.
I mean the whole attitude towards emigracion among the Mexican upper class is one of near-derision. The US to them is twice-a-year trips to Disneyland or Vegas, and they don't want 3rd wavers f'ing up their ease of access.
It gets even more specific than that. Southern Mexicans, the Surenos, and northern Mexicans, the Nortenos, hate each other, too.