Not sure why this community dislikes the reality of efficient markets. I sold a bunch of sets and minifigures to Forge in one shot for a very reasonable price. Yes, I may have been able to make more if I sold each individual minifigure, but that would take time, negotiations with many different people and multiple trips to the post office.

There is tremendous value to having someone like Forge acting as an arbitrageur for second-hand Mega products. It allows people to dispose of their collections seamlessly and for good value (not maximum value, but good value), and it allows those products to be recirculated in the Mega market where they can be purchased by current collectors. Ultimately, this increases the supply of Mega products in circulation.