Recent 'changes' and problems at a couple of group curation websites, which exist outside of STEEMIT, have made me a little nervous - I believe they should raise your eyebrows as well. If you have given your Active Key, or Posting Key, to a website or entered it into an application, of which concerns have been raised, then you simply have to change your account password, and all your keys will be changed.
Remember to Save Your Password !!
Do not get me wrong, I am not trying to raise doubts about any project out there - great work being done by great people. There has been some somewhat slap-dash efforts that you may have experimented with, and changed your mind. Or you may simply wish to end your participation in a project - this is the safest means by which to do so.