If I had such a big ugly wart, I would certainly have had it removed ages ago. Getting up every morning, looking at myself in the mirror and being confronted by such a disgusting protrusion would have made me feel very uncomfortable or driven me insane.

Obviously the old man does not seem to care, hasn't yet noticed it, or has simply become so attached to this extra facial ornament, that living without his big ugly wart would make his life unbearable and perhaps even not worth living.