When i got mine, although a 3.0i se roadster, it only had the 3.0I badge on the passenger side as well. I just assumed somebody stole it at some stage ?. I have both now though.
I am sure somebody will be along soon to provide a more definitive answer.
Mine only had one on the drivers side they did not all leave the factory with two will have to ask my mate who works for BMW why this was he did tell me just something BMW did.