What do you do with it all?
Some does go to its intended purpose, to the under privileged.
Some gets sold into industry, so for example t-shirts, will be cut into rags and sold per kg.
Some come in with the intent to be resold per item.
1 and 2 are done legitimately, everything will have been cleared legally for vat, tax etc. So for eg, the company buying bales to make rags, are not allowed to resell items as complete. It is quite strictly regulated.
3 not so much. There are often raids where the items are resold. The siezed items are cut up and destroyed. Resellers buy per bale, and that is their sole income. Most don't sell with a massive mark-up, so items are getting re-used and not going to landfills, but someone made a buck on the way. Is this right? I don't know, but people are buying more second hand items and less new. There are pros and cons to this. Of course the items are not coming in free. Someone somewhere has paid out for the bale and the shipping, and then the duties.
This, Shein, Temu etc has had quite a knock on effect on the local textile industry. As a result our government has just introduced a 45% duty on clothing coming in to the country. I am not sure how / if this is affecting bales though as it was just introduced this month.