You are right, it isn't conclusive to him having a history of burglary.
Looking at houses add up?
I'm sure Trayvon was a wannabe real estate agent.
When I was a teenager we used to go look at houses, should we have been followed?
When I was in Harlem an area known for crime I walked down the street to the bodega with my hood on looking at apartment buildings and the fire station, should I have been followed?
When I came back I was carrying a bag and I might have called my mom, would I have looked suspicious?
Tell me again why Martin was suspicious?