Bob's Addiction

I was reading up on the "bliss point", a sensory recipe for saturating the taste buds with salt, sweet, and fat molecules to maximize food attractiveness. But that's not important now; one of the items of interest uncovered in that research was that about 30% of folks, when they experience that blissful food, have such a rapid interplay between sensing the taste and the brain deciding it wants more of it that they lose control over self, and consume until the source of bliss is exhausted. Their brain becomes seized with desire. Onion dip does that to me. Is that a kind of instantaneous addiction?

I hold a theory that some percentage of folks are addictable. There are no doubt some substances that overcome our ability to control ourselves, and addict nearly everyone that experiences it, like crack, but that's not what I'm talking about. Rather, that in the normal course of events they will find a target for that addiction sensitivity, become addicted, and live their life striving to normalize around it. If they adhere to a bad one, they may try to replace it with a good one, trade alcohol for running, cocaine with the adrenaline of "the deal".

Is it true? Is it a nature vs. nuture thing? Does the percentage vary by gene subset? Are there genetic subsets which have culturally self selected over time for non-addictability? Is there a bell curve for addicts? Would we want to know? Would it be politically correct to use such information in policy?