Mine has been replaced TWICE due to the dealer scratching it while my EX was in for service. (I don't wear rings or anything on my right hand and nobody else had driven my car.) The second time, they documented on the work order "customer complains shift knob loose". I'm sure that was done so they could claim the part/service under warranty.
The last time I took it in for service, I was tempted to put a sport sock over it bound with an elastic but instead, I had the service advisor verify the shift knob was pristine and write that on the work order. I subsequently got the car back with no damage.
Anyway, all that to say that yes, it's prone to scratching and be careful because by now, Infiniti corporate might be clamping down on the rash of shift knobs being replaced under warranty.
You can have a look at this previous thread also:
zerothread?id=367963
Cheers,David