I use the "default" setting and never really had problems attaining the "cash-poor" feel at lower levels.
The trick at lower levels is to use the DMG system for determining the *value* of the encounter and then equipping it rationally. Most loot was in the form of gear (it was 3rd level before they had horses) with coin being thin and typically small denominations. Bows are *expensive* as are weapons and armors.
Heck, that goes for high levels too. I never give out 4d10x100pp. Ever. If there's 10,000gp worth of stuff then I'll have something like 20pp, 20gp, 50sp, 50cp and a 9700-something gp of gems, jewelry, or useful gear (masterwork strength bow+4). Most creatures won't keep large hoards of coin because it's too hard to manage or loses its luster due to it's commonness. Dragons are about the only thing that will have thousands of coins.
On the day to day level, most stuff will be in silvers. Don't say "half-a-gold," say "5 silver." Beer's a copper, wine's two, and dinner's a silver. Heck, gold should be a *hassle* since you can't get change. It's like buying a beer with a $100 bill at a dive bar. "Ummm, we can't make change for anything bigger than a $50." Platinum should be equally silly since you're waiving a $1,000 bill around. (Check how much beer & bread you can buy with 1pp. In my neck of the woods, it's about $1,000 worth of beer) Oh yeah, have money changers *charge.* Find a platinum, get 9gp back, or 4gp, 45sp and 50cp if you want to spend most of it on normal town items. Use of gold and especially plat is a big "rob me" sign. A rogue who nicks a single plat, by the RAW, now has about 3 months worth of city living (~1sp/day for unskilled workers).
Like people have pointed out, peasants don't live like most americans. I try to think about the US stereotype of Mexico. I have no personal experience in Mexico, but anecdotal information says that everything we have in the US is available there but the average wages are less like $25,000/year and more like $2500/year. Food, drink, basic clothing, and shelter are cheap but the pay is crap. Peasants are aware of the wonders of the world (TV, cutting edge medicine, the internet) but rarely have any for themselves. The slightest windfall can take you over the edge from peasant to adventurer.
So adventurers are loaded with coin and are used to living a 'luxurious' life. They also get shot, eaten, mauled, enchanted, beaten, burned, flash-frozen, and generally tormented. Fair 'nuff. Otherwise why, *in character* should most of them be adventuring? "See the world" only goes so far when most of the world you see is the pointy bits. And the love of violence can let you be a bouncer at a bar and bust enough heads to keep that itch filled by something other than three feet of steel.
I think if you change your treasure handling you can get what you want without massive rules changes.