>>8306761>>8306743Completionists. Whole teams won't go for as much as piecemeal since people who missed out a single member will probably be more desperate and thus spend more to get that last part than spend even more too get repeats with a complete set.
Funny enough, I actually made money when trying to get Optimus Maximus since I had 4 of the members. I bought a full set for around $120 and then sold each repeat member at $30 for the 3 limbs and $50 for Optimus, and also got Hot Rod for essentially free. People are just weird about money.