I tend to make treasure the target of a particular quest rather than just popping up (and leave it to chance, also known as the rules in Rivendell, whether anything of note arises, with a couple of rare exceptions which will be the object of a quest).

I don’t worry about having large amounts. The rules for encumbrance will make the journey back nasty if people decide to carry too much. How much to take is by itself an interesting decision.