Any assertion with the verb "should" is a moral/religious assertion.
These assertions are hypothetical in nature and based on a presumed, but not confirmed, future timeline.
(Contrast with evidence-based assertions)

Any assertion about how someone "should" feel about their choices is inherently a moral/religious assertion.

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Feeling superior over someone whom is different from you is usually predicated on a non-compassionate understanding of the other's motives and history.

Using your words and actions to intentionally diminish another human is a power trip.

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We all make mistakes; we all have quirks; we all embrace habits which could be considered self-destructive or anti-social.
(Shame on us, amirit?)

It's not like weight correlates to murderers or pedos.

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If I were convinced that weight or fatness corresponds to a definite increase in societal costs, then I would support a fat-tax.

Excuse me, sir, but are you licensed to be wearing a 42 inch waistline?
I'm afraid I'm going to have to write you a ticket for being over your licensed rotundity.
You can get this ticket waived if you apply for a "XXXL" license - and pay the associated tax, of course - at city hall by the end of the day.