Governments tend to be annoyed at having to regulate and will often ‘somewhat’ regulate the worst excesses and then do the equivalent of a staring contest with those regulated. If business push right up to the wire and fight every tiny loophole then they risk being hit with a second wave of much more severe regulations; if they generally comply and don’t embarrass regulators and politicians, then there isn’t need to spend more capital on better regulation. At some level it’s very costly to micromanage business regulation gestures at California but so there’s definitely some decisions to be made about How Far To Go Each Time that aren’t simply due to a lack of political willpower.
Or not. Who knows. The point is, this 'economically it is more efficient' is not a proven case because the externalities need to be taken into account, and so far the person I've been responding to seems to not understand this part, or is ignoring it.
The tradeoff may be worth it in some contexts, but if you don't understand that there are tradeoffs, you're going end up proposing silly policies like the original commenter's idea that nobody should ever be allowed to destroy any object a consumer could use.
If the benefit they get from waste is like 10% of the value they're destroying, then in a broad sense it is pointless.
And nobody is arguing against oversupply. Oversupply itself is fine.
Clothing is of course a bit easier to deal with (it'll still grow mildew if you don't protect it from moisture!), but the source link explicitly anticipates there will be some circumstances where it's impossible to give away clothing and authorizes destruction in that case.
This isn't some random guy. Their entire job is dealing with the logistics of big piles of clothes, and they have months in advance to plan.