How is "preheat" a marketing word? Every time I'm preheat the oven, I won't go "suddenly I feel an overwhelming urge to go buy a new oven."
If I'm shopping for an oven for whatever reason, I don't go "Oooh, this one has a preheat function!"
It's literally the word that I've used my entire life to describe the stage between turning on the oven and it reaching the set temperature. Language evolves, deal with it.
I've never heard of "prepurchase," what does that even mean? Like a free demo or something?
Expiration dates are approximate at best and occasionally only there to avoid liability, but I wouldn't say it's a "marketing thing." More like a "regulatory thing."
What's claro is that you seem to be bent out of shape over nothing, for the love of being miserable.