Before we age, we lack experience, context, produce less useful work per hour worked, and get paid less. Legality aside, isn't it rational to discriminate against younger people?
In 12 years in Austin I have encountered zero scorpions indoors, and maybe a single-digit number outdoors. This despite essentially constantly walking barefoot in both. In my entire life in Texas I've been stung by a scorpion exactly one time.
Mount it near the top of the door, out of reach of the small escape artist.
I had exactly the same problem and this solved it.