Posted by: gstamer on Sep-30-12 10:34 AM (EST)
Depending on what kayaking means to you, and where you paddle, it isn't always possible/practical/advisable to avoid scratches, no matter how careful you are.
My flatwater racing boats don't have a scratch (save for the occasional encounter with a submerged log) but my touring boats don't have that luxury.
Good luck finding a well-used poly white water kayak with a "showroom smooth" hull or an unblemished touring hull that has been used in shallow bays around oysters, for playing in rock-gardens, for surf landings on rocky beaches and for assisted rescue practice, etc, etc... While in some cases you can gently exit your kayak before you land, in many situations this is not possible or is life-threatening.
I treat the hulls of my touring boats like the bed of a work-truck -- they have a job to do. That said, all my kayaks (poly, glass and carbon) are "babied" by being rinsed after use and stored in slings out of the sun. As always YMMV.