Because they need a softer compund to stay on the belts. I used to run retreads on my XF, they did stick way better than radials, and they got worn out quickly anyway. I had also gone a far bit over the 140km/h rating on them as well, private road of course!!
Retreads smoke much better as well, but i'm not sure what would happen if you pop one during a burnout.
I've seen 235/45R17 retreads for about $80 each.
95 EF Fairmont 5.0 - Heritage Green - 4 Speed auto with AU S5 - 3.23LSD - 17x8" LWT Wheels - King Superlows - 76mm Cobra MAF - 65mm throttle - BPT Underdrive Pulley Kit - 3" Mandrel-bent Lukey exhaust - Tinted Windows - MP3 CD player - White faced dials.
117rwKw - firstname.lastname@example.orgMPH