Probably because if I'm adobe, I make money off people buying new versions of my software and I don't want to rely on some packaging system I don't have full co

Probably because if I'm adobe, I make money off people buying new versions of my software and I don't want to rely on some packaging system I don't have full control over to push people to upgrade. I want to be able to upsell the hell out of my users right from within my app.