I don't know if it's boilerplate in Texas divorce documentation or not, but it wouldn't surprise me at all. I wrote the custody arrangement for mine, so mine was definitely not boilerplate, but the judge who handled the initial hearing tossed out the "no drugs, no alcohol" prohibition as a casual afterthought, with no request to do so by either party or lawyer, which made me think it was very common.
Advice I had already received here on this forum, BTW.