Simply because. I am a fan of the U of Miami Hurricanes. Moving to Fl in 1976 after being released from the USN, and living in Tampa, where I am still, I traveled the state to see each of the big 3 football schools. UF just made me puke by the arrogance and sneeriness of a bunch of blowhards that had accomplished absolutely nothing up to that point, went to Tallahassee and watched the even more sucky Seminholers with the same feelings, then went to Miami and the Orange Bowl to see the absolutely horrible Hurricanes, but loved the atmosphere and the unis, so i chose them way before being a Cane was cool, and I'm sticking with them.
Being a charter season holder with the BUC-CAN-EERS GO BUCS! since day one in 1976 pretty much 'splains that. 40 years, mostly miserable, but they be my team.
The O's always - my dad, a born and raised Baltimoron, lead me down that path. Not a dreaded TB Rays fan at all, but I certainly respect them.
TB Lightning just because they started here, and I like 'em.
When it comes to sports, IMHO, no one needs any logical reason to like or dislike teams. It's just the way it is.