Yes. That.
The leader has the potential to turn rogue (that's what essentially happens in capitalism - someone in the chain becomes exploitative and decides to exploit workers, evade taxes and all). Same can happen in socialism and one way or the other we are looking at capitalism.
Exploitation of workers does not equal capitalism.
Capitalsim is the free exchange of goods and services, with prices and pay determined by a free market.
If you have a manager under socialism secretly stealing from the gov't and/or the employees, that is just corrupt socialism, as there is still no free market.
If a free market, say a capitalist black market (goods, services, and labor), were to arise, there would be a case along the lines of what you are suggesting. But, this, then, would just be a rejection of socialism, replacing it with capitalism.
