Our group tends to use the first; it actually works out a lot smoother in practice than it seems like it would. Rewards in a good session of Mutants & Masterminds or Warriors & Warlocks tend to consist or furthering of character goals or the acquisition of abstract wealth. The system itself favors extreme abstraction of wealth to include things like the concept of the warrior king with an ancient golden city as his base of operations or the idle prince looking for adventure; find a magical sword in a pile of treasure isn't something the game does well, though I imagine that if someone wanted to keep it, they'd buy it with character points. Afterward, though, I always figure the money goes to the upkeep of gear, a flurry of all-you-can-eat restaurants, and late-night benders with mighty-thewed companions and other forms of revelry (or is buried in the wilderness inside a giant barrel).