Duality is a term used here in Mexico. It means you can post naked women in your Automatic Tranmission shop, lesbians doing things next to the Blessed Mother of God. And when they sing the Ave Maria on the radio, everyone crosses themselves, light the candle and get holy. This thing of the school is true, and kids are confused. I've talked to high school kids who said their teachers insisted before the year was up, everyone needed to have a sexual experience, and find a sexual partner or multiple partners. Some of this influence comes to these rural areas via MTV. While others have gone to the USA and come back with navel rings and tee shirts that don't cover their parts. THIS is all part of why the people are fearful of going with the trends of globalization, loss of their values, and identity as a culture.
You're right...they do that. However, governments (theirs or ours) care nothing about morality.
It's not just in Mexico, mi amigo, here in The South we call them hypocrites!..........