> I have little privacy risk from the cashier glancing at my ID for a second to check my birth date.
Imagine your abusive ex is looking for you. She could go to a few alcohol vendors in the area and tell them "Respectful cashier, I suspect that my husband is reverting back to being an alcoholic. If you see the birthdate 1971-06-21 then please phone me after he leaves".
To which the vender replies "Why on earth would I check if someone over the age of 50 might be under the age of 18 (or 21 in some parts of the world)".
Well, I did have many more recent exes in my early twenties than I do in my fifties.
But also the mechanics of the check might be important. For instance, I always go to take the baby out of the back seat when I park, even though I have not driven a baby in years. Because I do not want to ever risk leaving a baby unattended in a car. The store policy might be to check every ID, even in seemingly obvious cases.
