There are non-smokers who use nicotine gum; I'm one of them. Similar effect to caffeine with a lower half-life, so it's suitable to have later in the day. I'm sure that we're a small group, but if nicotine didn't have the specter of cigarettes hanging behind it, I'd imagine it could be quite a large market.
Plant-based meat is sort of the opposite. Real meat has the specter behind it, so there's a good funnel of people into the product. Furthermore, any kind of taste that's above "edible" eventually gets people acclimated; they expect and learn to enjoy it. I can't prove that on an individual basis, but the plant-based meat market is growing at a healthy clip and has been around for several years, which suggests a lot of repeat buyers. You'd have to provide some kind of evidence to say "eventually they'll graduate", as there's no indication of that so far.