I know they cost a lot now, but just imagine how much they could be worth in the not so distant future. Especially if the MCU continues to become a thing of generations to come, like Star Wars, Star Trek, and James Bond.
I know as a movie series, it's already the most profitable there is, and once Spider-Man drops, you figure it's not only going to increase its lead in movies, but might be able to take the crown in franchise merchandising as well.
$3Bill well spent Disney.