Can't turn off Touch ID

[TomThumb333]

I've noticed after a recent update that Touch ID can be used to get into the app rather than the passcode. There is an option to turn this off, however even though mine has always been off, I get the prompt to use Touch ID every time. I've tried turning off the passcode entirely and then re-enabling it, but it doesn't make any difference. It seems that when passcode is on, you get Touch ID no matter what the toggle switch is set to. Is this just me?