Maybe Verizon and a couple of other carriers paid them to provide it.
Wow. It took you a while to figure it out.
Yes, that's exactly what happened. Verizon (and probably the others) and Skype entered into a contractual agreement for Skype to be available on their BlackBerry devices. Verizon PAID (presumably a lot of money) for the privilege. It's called business.
And again, you didn't use the word "supported" in your post. You said "I seriously doubt there ever will be skype for BlackBerry, except for BB 10. " which is wrong since there already IS "skype for BlackBerry".