How are they getting what they want? What communists (and in a lesser sense, socialist countries) want is less of a chasm between the lower and upper echelons of society. Just this day it was posted on Reddit that a top London banking boss will already have made more since the start of the year than an average worker will the entire year (!!). All UBI does is make sure everyone has a baseline to live from. That's great, but its just a sedative for the masses. You're a lot more likely to riot if your kids are starving.
I wonder what will lie beyond UBI. 3D-printers for everyone? Everyone can print a fancy car, a lobster, a new arm, etc.. which would basically make everyone completely equal.