It's amazing how granting one little request can stave off some serious shit. We've done the candy bar trick before, twice. Got a guy years ago to end a hunger strike with a piece of smoked Sturgeon. The guy was in isolation for constant observation which made it VERY easy to walk by eating a piece. The smell and possibly me going Mmmmmm this Sturgeon is good broke his will.
We had a couple good laughs after that, then it was back to Bologna Sammiches and a bowl of dirty water (soup). 
5-hour prison hostage standoff in Ireland ends after candy bar exchange
https://www.foxnews.com/world/candy-bar-ends-irish-prison-hostage-standoff-with-only-minor-injuries
5-hour prison hostage standoff in Ireland ends after candy bar exchange
https://www.foxnews.com/world/candy-bar-ends-irish-prison-hostage-standoff-with-only-minor-injuries