for once, even if someone claims credit, in most cases it's easy to prove that it wasn't made by the 'stealer'. If it isn't, then you are doing it wrong. Just hide your name and/or BL_ID everywhere in form of print bricks, events and stuff like that (make sure you use default bricks and events)
second, if someone 'steals' your build, then that means they find that build good enough to attempt to claim it. You should take it as praise, because in reality, it is.