Yes, I'd do it right away. Certainly, if you hit a snowbank in June or July, you'll have a problem. But the car won't be your problem. What a

, to even say that.
I would fix it, but come on. Snowbanks? Does he think that will make you hurry?
The reason I suggest body putty is that modellers use body putty to fill plastic models all the time; it's essentially an epoxy, and bonds to all plastics. Pick up a tube, and work on filling in the cracks. Or just pay the $200 and be done with it; what's your time worth?