Have had swollen ear lobes for a long time with no other apparent symptoms. is this unusual?

Yes: Can be related to piercings ( foreign bodies, earring in earlobes), allergic reaction to insect stings or cauliflower ear. This occurs after a blow to the ear results in fluid building up under the skin. These are the only causes I am aware of.

Yes: Typically ear lobes do not swell except in response to infection, allergy (contact dermatitis), or trauma (cauliflower ears from wrestling etc). You could also have a cyst in the earlobe causing a little swelling. Since you are probably not a wrestler, we can narrow the potential causes down a little, but I would recommend seeing a MD to rule out an infection/allergy/cyst.

See your doctor.: The causes of chronic swelling of the earlobes can range from an allergy to a metal in a new earring to low-grade infection and inflammation. Since the treatments differ, you need to see your doctor for the correct diagnosis and treatment. Best wishes!