At a pretty quick glance, and admittedly potentially faulty math ... Doesn't it seem like you can kind of buy the items in the Recycle Beast shop from user shops for cheaper than the smelting price?

4 millions gets 500 points. Ametsuchi costs 30,000 points. You'd need to smelt 60 times to buy Ametsuchi. 240 millions in smelting.

There are currently 3 Ametsuchi in user shops for under 100 millions each.

Afaik smelting has never been "worth" it, I only did it for the achievements.

The cheapest way to earn points is to turn in the items he is asking for, and honestly speaking I think the Recycle Beast items are generally hard to sell, so people who have bought one may have changed their minds and listed the item for a discount to get back pure sP (I'm not super familiar with pricing of Ametsuchis so I'm not sure what is the normal price)

Ametsuchis usually sell for around 70M-75M these days.

Interesting point! If your calculations are accurate, it seems like the user shop prices for Ametsuchi are significantly lower than the cost of smelting. There might be other factors at play, such as potential fees or variations in item quality, but it definitely appears to be an arbitrage opportunity.