This is worse with web but is old as time.

It used to be common for ingredient sellers to issue recipe books that would extoll the value of their goods, trash their competitors', and the recipes would usually include the ingredient even if it didn't do anything for the particular food you were trying to make. (E.g. "our flour is pure, unadulterated, and not bleached using toxic ingredients unlike our competitors who also eat babies", which was a more effective marketing tactic before the existence of food regulatory authorities curbed the worst excesses.)

The recipe on the side of the box is a much smaller-scale version of this.

It's also a sales tactic. Mary Jo Rose is selling you her story so that you will buy the idea that you should subscribe and keep reading her posts even if you have nothing to cook, and eventually use her Amazon link to get 10% off paper towels.

yes, that would also serve SEO - longer on the web page + more content viewed = greater "engagement"