Not really an issue on my S5
Being that the fingerprint reader on my S5 rarely works anymore, even if some crim were able to scam my fingerprint, they most likely wouldn't have any better luck unlocking the phone than I have had.
In fact, it is so bad now that I don't even use it any more. Now use a long PIN.
After having it fail to read the registered fingerprint, one has to wait 30 seconds before trying it again. Only to have it fail again and resorting to the backup PIN or password you have to include when registering a fingerprint.