It sounds convenient but, in fact, this software is full of failures, bugs and viruses. Thus people don't need to buy Adobe Illustrator to take advantage of its features.
Most often, the software available for downloading and labeled Portable is an illegal pirate program which was hacked. All portable versions of Adobe software are unlicensed modifications created by users. Adobe hasn’t created an official version of Illustrator CC Portable. Illustrator Portable is the unofficial name given to modified versions of Adobe Illustrator for Mac and Windows that can be launched without an installation.