Exocytosis DOES require energy. Think about it, you're breaking and forming chemical bonds. Not to mention getting the vesicle to the membrane, binding it, incorporating it, etc. etc. It's not actually just some fatty vesicle that floats through the cytosol and binds willy nilly to the membrane then it's out. If you are interested in it though, it's a fascinating process and a good cell book would have it in there.
It's a lot more complicated than that, but if it is on the MCAT it will be in a passage.