I don't see how it would make a difference unless the concentrates are not pg or vg based?
Edit - I see now it's alcohol based.
Sorry, been out of it for a couple of days.
Actually, I really don't think it makes any difference, myself. Manufacturers of the less potent PG- and VG -based flavourd take the concentrated essence (usually from some other manufacturer) and dilute it down with PG or VG.. So the flavour essence does feature in all the recipes by implication, without it ever appearing as an additional diluent in any recipe.
If you click on "Recipes" underneath the flavour notes for any given concentrate, you can see examples of other people's recipes, using same flavour
The advantage, for the consumer of thinning it down like that is comes pre-steeped, to a degree, and you often wind up with a shake-and-vape; talking of which, I've recalled a great UK manufacturer for VG-based S&V flavours:
https://www.justvape247.com
They have own-brand PG-free lines. Kandi-Hed , which comes in a choice of PG-based or VG-based, recommended usage 20%; and Angel's Touch, a slightly more concentrated organic range , diluted in aqueous glycerine (VG + distilled water), recommended usage, 15%