Its buying all the content (all characters, DLC characters and costumes). Technically you could get Xbone and KI then weekly/bi-weekly have a different character to play with.
Your BBY most likely is one of the "Showroom" best buys. Mine is like that because they are a "showroom" for appliances and such. Luckily I have another on the way to work that maintained its "normal" status and has a decent selection of everything.