Why not more OEM offset?

Help me understand this. Ok, so the TRD Pro wheels have a greater 1/2 inch offset. I understand why (I know what offset is, etc, etc).

My question is, why not do this on other models? I think all members with OEM wheels would agree that an extra 1/4 or 1/2 inch of offset would be great.

Toyota offers it on the Pro models, so it must be a good thing.

Is there a reason why OEM Tacomas appears to be a bit negative in the offset? There has to be some benefits, no?

 

i went thru 3 sets of rims on my pro in 8 months, and as many sets of tires, it never had the look i wanted, untill i purchased a set of SCS wheels.. wider stance, awesome looking wheels,, if i had purchased them after selling the oem wheels, i would have not bought the pro sema wheels which looked nice . but the offset wasnt there,,, love my SCS wheels,