But vanilla plants contain a lot of other flavor/odor chemicals (like anise alcohol/methylguaiacol, p-hydroxybenzaldehyde/trimethylpirazine, p-cresol/anisole, guaiacol, piperonal) in addition to the one primarily chemical (vanillin), which may also be desirable in certain applications, such as foods or perfumes.
I would have no problem buying 750 mL of 40% grain alcohol loaded up with sugar and artificial vanillin if I'm gearing up for a giant bake sale or something, but I'd still keep the 10 mL bottle of the real stuff for finishing sauces, frostings, icings, or beverages.
Important caveat, though: vanillin derived from engineered bacteria or yeasts may be eligible to be labeled as "natural flavor"!
( https://www.topatoco.com/merchant.mvc?Screen=PROD&Store_Code... )
In many countries there are legal requirements for "Vanilla Extract" vis a vis the percentage that comes from vanilla beans, as opposed to "Vanilla Essence", which can and is typically artificial.
(I confess I bake a lot)