What do you mean you can't turn off BT? Do you mean that you are unable to turn it off with either the quick settings button in the navigation bar or the toggle in Settings under Connections? Are these options greyed out, the setting doesn't stay after you've turned it off or do you mean something else?
What do you mean turn off the "scanning thing", at locations? Do you mean that when you arrive to a location that it begins scanning for devices to connect to? Devices cannot connect to your phone unless you accept the connection or they have already been paired.
It sounds more like you're talking about WiFi and not BT. BT doesn't scan unless you ask it to. It is also not typically searchable unless the device is in discovery mode. WiFi on the other hand will scan anytime it is on and not connected to a network and typically has an annoying pop-up that lets you know there is a WiFi connection available even when you don't plan to connect to a public network. WiFi is also known to turn itself on, usually in cases of weak network signal, to try and keep the device connected to the internet.
So do you really mean BT or do you mean WiFi?