I always noticed this on every 911 and BMW 3 series you see too. What I try and do is put my butt in first toward the end of the seat and then slide in, down and around into the seat back, avoiding the bolster completely. Have the car 2 1/2 years (true only 6,000 miles) and NO sign of bolster wear at all. Avoiding black or dark seats helps a bit too, you don't see the cracking as much.