Changed candies material to null

As per the discussion here #5510 I changed the material of candies to "null" from "veggy" until a proper material type for junk food get flagged.

What I changed:
-All the chewing gums (including the mint-flavoured).
-Some snacks with chocolate.
-All the candy, including the one with "peanut butter cups... ".

Tell me what should I add, or revert back to "veggy" from this list.