As long as you always have the option to exchange money for something useful (or at least know that you will have the possibility when you need it), you are indifferent between getting the item or money to buy the item.

I don't think this works correctly... your agent has money and is standing next to a soda machine, getting progressively more thirsty. How does that trigger the exchange if you tie utility of money to utility of water to drink?

The thing to remember is that utility is what you use to push your utility maximizing agent around, to make the agent do things. The agent has some foresight of how it's actions are going to affect future utility, and picks the actions that result in larger future utility. For human, the utility may be some integral of quality of life over the possible futures. Drinking water when thirsty, eating food when hungry, living in a better house vs living in a worse house, that sort of stuff. Use, not passive possession. If the agent has descendants, or cares for the mankind, then the integral may include other people.

If you include possession of money over time into this integral, your agent will make trade-offs between possession of the money and the ultimate total comfort of his life (and those he cares about). The agent's behaviour will be that of a miser.

edit: and yes, as a heuristic, you can assign derived utilities to stuff that can be exchanged for usable stuff. But you can't include those utilities in the sum over the original ones. The derived utilities are a shortcut, a heuristic, and one needs to be careful not to sum together utilities of different types.

edit: to think about it, though, maybe a great deal of people have the kind of utility that you described here, the utility calculated from possession of items. I, personally, try to act according to the utility as I described above, calculated from the uses and comfort of life.