Only because the econobox market is there to feed it.
Anyway a bigger fwd car would be boring compared to other cars not yet in LFS, like a Corvette or M3 or something muscle-ish (no real meaty road going engine cars in LFS yet) like a Monaro, or F430/Cayman, or AWD MR like Lambos, or a roadster like the TVRs or Weismanns, or an LMP racecar, etc.
The only fwd cars that've gotten unquestioned driver's car status are the Mini, the RS Focus... Maybe a few others but definitely dwarved in number by models of other drivetrain layouts, especialy F-RWD. There aren't any FWD supercars because it's an inherently bad layout. It's meant for cheap mass production, and has been adapted to racing, not the other way around. This would be apparent in the relative sluggishness of a car like the big heavy FWD sedans.