What is the most succinct term for "refusing to take the bad with the good"?

Solution 1:

The closest term I can think of is opportunistic: (from TFD)

  • Taking immediate advantage, often unethically, of any circumstance of possible benefit.

Solution 2:

To answer an idiom with an idiom, this would be someone who wants to have their cake and eat it too—they want to enjoy a benefit without suffering the attendant negative consequences. This expression is usually employed pejoratively, so if you're looking for something with a more positive connotation, you wouldn't want to use it (although maybe you could get creative with it).