I didn't accuse you of that.
Shadowrun has a purchasable lifestyle cost, which meant you simply deducted that money per month, then looked at your supply of cash and realized you had better get out there and do a job soon.
Games that don't have these easily calculated expenses (like d20 Modern) can get very tedious if you try to track expenses (each meal, gasoline, etc). In D&D PCs tend to buy food but otherwise sleep in a ditch in the woods, probably without even a tent to keep themselves warm. They don't pay for horse feed because they don't have horses. This isn't necessarily because PCs are desperate to avoid paying a few coppers, but keeping track of the tents, meal expenses, etc, would simply take too much time, compared to the time spent buying magic items. (Pathfinder 1e did a good job with "equipment kits" so at least in those games PCs tend to have cooking pots and tents. However if there's an easily calculated monthly expense, per social class, I didn't see it.)