Well, now, their opinion of language, holidays, and culture may be as you say. It doesn't change their opinion of the people, though. I suggest you come spend a day or two with my daughter-in-law and her family for a real eye-opener. Her dad is of Spanish descent; his family settled in Holbrook, AZ. Her mom is of Mexican descent, her family was 'trapped' on the US side of the border in Bisbee, AZ when that border was closed at the turn of the 20th Century.
Her grandfather took part in the Bataan Death March, escaped and lived to take part in guerilla actions against the Japanese in the Phillipines during the latter years of the war.
Theirs is a very American family and their utter disgust at the effect of illegal immigration and the mean nature of illegal immigrants in Arizona is palpably opposed to your observation.