the reason is that a mould for the bonnet is alot more time consuming to make and requires alot more material due to the fact that you need two moulds to make a bonnet. the bottom mould and the top.
if you look close up on an after market bumper u should find that most now days have something wrong with them..for example the surface is wavey, twisted/warped or out of shape. with a front bar u can get away with this kind of stuff but with a bonnet u cant.
i guess if ppl wanted a cheap bonnet it could probably be done but would u be happy with the quality? drop the bonnet down and it cracks? or it doesnt close properly?
i wouldnt want to be driving one day and the latch bakes off.
so if u can find a front bar brand new for around $400 or under..
anyway the r32 mould has taken around 3weeks now and its still not complete.
the guy has put heaps of time into it trying to make it perfect.