Its normally stress/boredom that creates habits like those. You mentioned he may have a UTI, so he may be pulling at hair because of discomfort. With his background i would keep a close eye and deffo get a urine sample sent off for analysis.
George had huge balls, until i gave him a good groom and found out 50% of him was hair!
he was a dirty stray and never washed except his face, front paws and the white bit on his belly
i never took photos tho!