What i call a ''Vet Check'' is basically handling your dog and getting them used to your handling them in all areas of their body, from teeth and ears to feet and tail. Wounds can crop up anywhere and if your dog is better adjusted to being handled then if the need for eye drops or ear meds comes up in their future you will be better equipped and it will be much less stressful for your dog.
It also builds trust and a solid bond between you and your dog so why wouldnt you?