This is the essence of the moral argument: Someone chooses to abuse a substance, they become a more frequent abuser, and the abuse piles up damage, which the person ignores to continue abusing.

The essence of the argument against drug interventions is that the root cause is personal choice, and therefore a drug is a shortcut or crutch and does not address the root cause.

Many people feel that the real cause is the structural changes to the person's brain, body, and daily routine that reinforce, and are reinforced by the initial tiny over-consumption, which compounds over time. It's like a debt where you are stuck paying interest, no matter how much you'd like to pay off the debt. Addiction is a system in which the person's willpower goes against everything they have set up over decades. It's unreasonably challenging for nearly everyone to walk it all back. Insulin resistance is one of the most pernicious effects of even small over-eating over time. The body and mind do not feel satiated even though enough calories have been consumed. It's not "I would enjoy another slice of pizza", it can be "I am still starving".

And yes, the environment in which we live, where it is less stigmatized to overeat, and food is treated a certain way, more like a drug than fuel, is part of that system.