I've got a few friends on my list who obviously have hacked towns (100 of each car, 10 Lard Lads etc) and all of them have very cluttered non-thought out layouts, with everything just crammed together to farm cash and XP.
To me that seems like a complete waste of time, the fun of the game for me has been waiting for things to build, waiting to have enough donuts to buy new characters and trying to make my Springfield look and feel like a REAL working town. It took me a long time to cave in and start buying donuts, but the scratch cards are just too tempting!
I've probably been playing the game almost a year now, slowly building everything up and making the town feel right - if i'd got everything all at once, i'd have had no idea what to do with it all!