Mainly because their absentee fathers looted their mother. They are using the skills passed down to them. The other reason for looting is the war between civilization and anarchy, the "haves" and "have-nots".
As you point out the have-nots have plenty of the essentials and even non-essentials . But they are taught by the militant anarchists on the left to despise the gilded class, who in the future you describe, will be the robot owners. The leftists will be just as gilded of course, but they won't produce anything and won't own the means of production. Therefore I would anticipate that even heavily guarded means of production and distribution: robots and robotic conveniences, will be the first to be smashed.
That is why I do not see as rosy a robotic future of plenty as you might. The robots have to remain unsmashed. The goods produced by the robots have to make it to the recipients without being hijacked along the way. Since smashing a robotic truck won't result in any loss of life, the crime will not be prosecuted vigorously. I predict a future of random, nonsensical scarcity within an overall relatively efficient supply chain. Maybe the latest iPhone, stolen or looted will be traded for a sandwich looted from the automated restaurant. The restaurant will be rebuilt, but even more automated with even fewer human jobs, lower quality, more government cheese as the main ingredient, etc.
The destruction of the Black Family is caused by the Great Society. With Uncle Sam, who needs Daddy?