@click here,
It's not a big mystery. Some atheists beg the question, some atheists ask rhetorical questions, some atheists are stupid... just as some theists are. That is, if you're asking a question about some people's psychology. But even though you pose your question that way, it seems to me you're trying to make a point, albeit in a roundabout way, disguised as a question. And the point might be: "Hey, the argument from evil is not a good argument against the existence of God as the argument merely assumes (and therefore begs the question) that God's existence is logically incompatible with the existence of evil." Or something like that.
Is that the sort of point you're making? If so, which atheist are you talking about and which argument from evil? There are many variations, in fact a whole study of this argument pattern--the argument could go in many different ways. Any in particular you want to talk about?
A lot depends on what you mean by "God" (rather, what qualities you're associating with this concept) and what sorts of evil we're discussing. For example, if the concept involves the 3 Omni's (omnipotence, omniscience, and omnibenevolence), then the issue might be framed: Why couldn't a all-powerful God create a better world than this? Surely an omnibenevolent God would want to if He only could. Now that better world might be one with no evil at all, or at least with less evil, or with only the "necessary" evil. Now the discussion could go on many directions regarding how the world could be better (do you really believe this is the best possible world with all that suffering?), or what evils are logically necessary if this were to be a "good" world (if any are necessary at all). For example, some theologians have thought that evil is necessary if we are to have free will (which presumably is a good thing). But even then it's not clear why there has to be so much evil. Was it really necessary for 6 million Jews to be tortured and killed in those concentration camps? If God were to intervene and spared some of them, how does this negate free will? I mean a parent can stop a kid from torturing his brother and that intervention would not negate that kid's free will (either entirely preventing it or stopping it once the parent sees what he's doing). Even worse, how about the kinds of evils NOT caused by humans? Like natural disasters--earthquakes, floods, etc. These create a lot of suffering. Why are they necessary? They have nothing to do with free will. Why is it impossible for an all-powerful God to create a world without floods, earthquakes, etc.?
I suppose you could say I'm begging the question too when I ask these questions, seemingly rhetorically, because I don't see why such evils has to exist. And I suppose you're right; all arguments are question-begging as they ultimately depend on premises the arguer takes for granted. But if you were to make theistic arguments, all your arguments would be question-begging too as you're making use of premises you take for granted--premises that others would deny. Welcome to philosophy, heh.