That would be a solid line of thought if this would be some shady adware from some unknown company. But Dropbox is valued more than $10B, that's more than twice the market cap of all Bitcoin. Even if everyone at Dropbox went criminally insane, there would be no way for them to recover even a reasonable fraction of it in BTC markets. Not to mention it would completely kill their reputation and thus the highly-valued business.
Lenovo is a $16B company, and we learned they're breaking SSL and man-in-the-middle attacking all their customers. I think we should be careful in not assuming "big, rich company" means "sensible, responsible company"
Also, theoretically, it could be a single (or a few) developers going rogue, rather than an approved company policy. It wouldn't be the first time.[0]
Collecting "metadata" such as Address X stored on Computer Y on ip address Z could be worth quite alot to likes of NSA who I am sure have plenty of incentive to monitor crypto-currencies and would either pay Dropbox to do it or alternatively bang them over the head with a hammer and make them their bitches in order to collect all sorts of juicy "metadata" on millions of people world wide.
Hell access to so much information could make for quite a political tool, remember that general in washington who was kicked out because he was having an affair and somehow his private communications via gmail drafts became public. What would prevent an opportunistic dictator from gaining absolute control over political landscape of a country if this dictator has access/control to an organization such as NSA?
Americans get up in arms over their right to be armed all the time, but they ignore (or do not realize?) that without privacy and secure communications they would never be able to organize a resistance to a totalitarian government which is better armed and could potentially (already does?) monitor everything and everyone on a scale that would make Orwell blush and spin in his grave.
