What about all those hacked servers that we don't know that are hacked yet?
There are ( and I'm pretty sure ) lots of hackers that do this on a daily basis, but don't try to do anything malicious on a large scale ( like dumping the whole db of customers, DDoS, etc. ). They probably target medium-large or small companies' servers, put a backdoor there and analyze. Either stealing some business secrets or leave it like that for one of the dark days when some political-corporate person will need their help.
Having the whole human knowledge on the palm of my hand made also our own lives public-knowledge.