Re morale boosts: not everyone uses any given morale-booster, too. Marijuana, LSD, etc, see zero use from me. Booze only if Ka’lol has Ethanol Burner and Blood Filter.
Candy…yeah, if there’s a need for food/sugar/extra morale NOW. if he’s training combat, the mp3 player ususally gets the nod. I put in the other candies simply because I personally don’t much care for peanut-butter cups and resented having to have them as my “favorite”. 
(Wouldn’t bother with mayo, either. RP choices FTW.)
Back at base, books are probably it. I’m liking SF and Fantasy, now that Romance got nerfed.
Why bother? It’s nice to keep Focus up and get out of ): territory.
You could accomplish a similar result from having Boomered/Walked In Sewage/etc apply morale penalties.