storeagent downloading meaninglessly?

I just noticed storeagent is downloading at about 1MB/s, while no disk activity & no memory usage increase(I mean if you are actually downloading things, you gotta write it to disk right?). Here's the screenshot. Is it a bug or something?

BTW, my Mac App Store in 10.9.1 is really screwed up. Updates are not showing up in the 'Updates' tab while I can click the 'update' button under the 'Purchases' tab. Is it just me or it's a common bug?