This theme of anecdote has been trotted out for more than a half century. In the 80’s the yarn was that a supermarket could tell when a woman was pregnant before her doctor from her purchase patterns alone.
To this date, no supermarket has ever produced this result - or any thematically similar.
Target’s able to confidently estimate that a woman is pregnant from 20 weeks from their purchase history, if they’d purchased pregnancy tests. A doctor can tell you 70+ days earlier.
They’d probably have an equivalent outcome if they just looked at cctv footage and guessed based on weight gain.
To this date, no supermarket has ever produced this result - or any thematically similar.