You are probably right that it is not an alergy as he is licking other things besides himself. He is probably just bored. I would give him a little more excersize everyday and some stuffed kong toys, rawhides, buster cubes etc.. to keep him distacted. It can turn into a compulsive behavior & then the sores are known as lick granuolmas (spelling is bad lol).

One of my dogs is a licker too, he likes to lick the heat registers & he chews his feet (just like some chew their fingernails). Sometimes he is a carpet licker too. He is not obsessive though.