I always thought that too. Sounds just like polka, and easy to dance a polka to it. A lot better than rap anyway. A lot of Czech and Germans settled in Texas in the 1850s and Mexicans adapted the European culture!
It really is a Tex-Mex thing, and Mexicans far removed from the border consider Norteña be old fashioned music for hicks and rubes.
It should be noted that National Polka Festival is held a each year in Ennis, Texas. Texas has the largest concentration of people in of Czech descent in North America.
Yes, I've made it to Westfest a few times, and always stop by the Czech Stop for Kolaches when I'm driving back to DFW from Austin or San Antonio.