I don't see any danger in using a fingerprint as additional layer of protection, why would that be dangerous?
Sometime 'more secure, less comfortable', protection with biometrics will certainly provide a double level of security. However, biometrics on the other hand is very sensitive to changes, for example when we experience injuries and there are changes to our fingerprints, it can be that this method will not work optimally. Just opinion.
Thats true,nothing is 100% safe, but i still think that we are going in right direction when it comes to security,its still better than just password protection.
People often forget or don't even consider that safety of their data is 100% down to them.If you are taking care of your data and educate yourself your data will be safe.