"The two faces of Bill Gates parallel the two faces of Soros. The cruel businessman destroys or buys out competitors, aims at virtual monopoly, employs all the tricks of the trade to achieve his goals. Meanwhile, the greatest philanthropist in the history of mankind quaintly asks: 'What does it serve to have computers, if people do not have enough to eat and are dying of dysentery?' In liberal communist ethics, the ruthless pursuit of profit is counteracted by charity. Charity is the humanitarian mask hiding the face of economic exploitation. In a superego blackmail of gigantic proportions, the developed countries "help" the underdeveloped with aid, credits, and so on, and thereby avoid the key issue, namely their complicity in and co-responsibility for the miserable situation of the underdeveloped" (Violence 22).
Gates "give away your wealth, billionaires. It's fun!" rhetoric focuses only on subjective violence - violence, as Zizek writes, "which is enacted by social agents, evil individuals, disciplined repressive apparatuses," etc. The "do-this-now-its-fun" call distracts attention away from the systematic violence nestled at the root of capitalism. Zizek writes, and I think he's right, that Gates call for a friendlier robber baron "signals a sad predicament of ours: today's capitalism cannot reproduce itself on its own. It needs extra-economic charity to sustain the cycle of social reproduction" (24).
That is not to say that Gates money will not do some good. I imagine it will do and has done. However, I do think it is a distraction from the real issue, which is the massive global economic exploitation necessary to produce Gates's wealth in the first place.