A full cat-back for my YJ costs about $500 (incl exhaust, headers, etc.). Most guys I see slap glass packs on their import and spend money on speakers rather than true performance accessories.
HR - you know I'm just joshin' about the rice burners. Whenever I see one, I think they are probably laughin' at my 6" lift and 36" super swampers on the mud buggy. It's fun looking down at them though : )
Don't sweat it, until I bought my Probe & my MX6 I thought the same way you do. What happens is that when you break down & buy one (a descent one that is) you find out that you can compete with the V-8's & you can also get 20-25 miles to the gallon and trust me when I tell you that's just what happens.