Many games typically only use between 2mb - 12mb an hour of play time. More typically in the middle, which is what your seeing. MMOG's send lots of packets, but they typically are very very small. So you see your network adapter blinking like mad when you play but that's because it's getting and sending thousands of tiny itty bitty packets back and forth. So in the end, most MMOG's just don't use up a lot of bandwidth, which is why one household can have 5 people playing on just one DSL line and nobody is the wiser.
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