Yes, absolutely. The Texas state title 6A game (the largest populous high schools are classed 6A and then down 5A and 4A etc for clarity) is now held in the Cowboys stadium every year and as you say draws close to 50K. American football is huge in the southern states and is so dominant that all the big universitys in that region dont have mens soccer programs as their scholarships are all used by the am football programs. Powerhouse universities like Univ of Oklahoma, Alabama, Texas, Texas A&M, LSU and Auburn all have top womens soccer programs but none on the mens side. As such, the high schools as you say in places like the Dallas metro area are mad for their high school football. Google Allen high schools stadium (a suburb north east of Dallas) and see pictures of their $60M stadium for proof......and that was built 8 years ago

Consequently, high school soccer takes a massive back seat there, even though Dallas especially has some of the best youth soccer clubs in the country like FC Dallas, Dallas Texans, Andromeda FC, Solar SC and a not so good club called Liverpool FC America.