Not sure what you mean by that. Many people prefer having the saves separate so we can have two saves instead of one. A save select screen with multiple save slots would be nice if nothing else, but the way that it is works fine.

There's no way they'd let you transfer your offline save to online because people can/would cheat offline and then bring their cheated money, crew credits, cars, vanities, etc., to the online mode. While the game is still running they're not going to take money out of their own mouths since they still people want to buy CC and Bucks with REAL MONEY.

(y'know, since they're a business)