Your nieces sounds like very imaginative kids, Maleficent! Playing make-believe is an important step in socialization and becoming an adult, so when kids choose video games instead, an important part of their development as individuals is merely glossed over, if not completely skipped... I hope your nephews come around eventually!
(I would have included more gift options, but you can only do 10... plus, books should probably be a given anyhow
)