High-Society Socialism
Socialism is about wasting earned money. Heirs didn't earn their own money. If you go beyond what they preach, you'll find out that the entitled upper class invented Socialism because their mindset, and their experience, tell them that everything is an unearned gift. Because of their own unearned wealth, power, and influence, they hate the concept of earning and merit.
There's also the influence of being so spoiled they impatiently want everything right away and as much as they can get, any way they can get it. Typical of Leftist leaders, Castro's father was absolute boss over 200 people. Because of the laws you're made to believe in, Fidel could have inherited that position. But, being typical of spoiled-putrid richkids, he wanted much more and and much more quickly. So he got to be boss over millions at an early age.