For my purposes, this applies explicitly to running a published adventure like Out of the Abyss, but a general answer would also be useful.
When the party has a random encounter with a non-humanoid away from it's home/lair, is it supposed to have treasure? If so how is this implemented? Most monsters don't generally walk around with a money purse or carrying magical trinkets or spare weapons or any "treasure" whatsoever. I have done the trick of having the party find treasure on the monster's previous victims in the past, but for many random encounters where the creature is not "at home" even that doesn't make sense.
The DMG treasure table (p. 136) suggests that any monster of a given CR should have a random number of coins according to its CR, but that doesn't really "make sense" for a lot of random encounters.