The lacquer that is peeling off is actually a very special product called a 'hardcoat'. Polycarbonate, from which almost all headlight lenses are now made, is actually very soft and will scratch incredibly easily. The hardcoat is applied to protect the polycarb from stone chips and scratches that you will get from everyday driving conditions. This is required to prevent the lenses getting so scratched that they start to produce glare for other road users. The lacquer is applied during the manufacturing process of the lens as the whole thing needs to be cured in an oven at a temperature where parts of a complete headlamp may start to melt/ deform.
Removing the hardcoat is not a very good idea as you will find that you will forever be polishing out scratches, also, on older headlamps it acts as a UV filter to prevent the polycarb from yellowing (newer formulations of polycarb have a level of UV resistance built in, but over time will still yellow if unprotected). And a normal paint lacquer will still scratch and chip, take a look at the swirl marks in your paint work that you all keep having to polish out!!
Sorry to say, but if you want a once and for all fix then it will need a new headlamp, however you may be able to argue that it is a warranty failure, as the hardcoat shouldn't flake off provided that it was cured properly in the first place. We had a lamp returned to us under warranty that had come off a Land Rover in Saudi where a sand storm had completely stripped the hardcoat off the lens and this was changed under warranty so it's worth a try...god knows what the paint work on the rest of the vehicle looked like after that!!!