When designing an Utopia, one needs to consider also how people who do not fit in are treated in the Utopia.
One way in which someone may fail to fit in is by being unsuccessful when trying to play by the Utopia’s rules.
In capitalistic regimes, unsuccessful people are poor, hungry, have poor health and bad (or nonexistent) housing. They then have a good reason to try to overthrow the present regime, in the belief that in a better regime they will have higher quality of life.
Another kind of unsuccessful people are those, who do not have the patience and long attention span to build their wealth slowly and on solid base. Such people indulge in various get-rich-quick schemes. They typically become real estate and insurance agents. They start the classical makework businesses. They do not consider the benefit to society when planning their business, only how it can funnel money into their pockets. Such people are behind business scams and Enrons.
A third kind of people are ones, who are better at organizing (i.e. influencing) people than in creating something. They become salespeople and politicians. They are the ones, who might believe that their personal success would come from organizing poor people to overthrow the present regime.
The real test of an Utopia is in how it deals with all those kinds of people and how can they find their opportunities in it without harming other people.
At any case, there will always be some people, who feel very dissatisfied with the Utopian regime, and who would try to overthrow it, or at least get it to change. Such people are necessary for the future evolution of the Utopia and for updating its workings according to the changed times. Those people would be good at pointing out abuses of the establishment and at getting it to change before it is overthrown.