If the full price is €6, there isn’t much room for a discount. Destroying and freeing up store space for something that does sell can easily be profitable.
Not at scale. Charities only can move so much merchandise themselves, because only a small slice of the population goes to charity shops and/or accepts charitable donations.
Allllso maybe the junk that is trashed by Zara is just junk that charities don't want to be burdened with?
