Logmnr constraints disabled

Can someone tell me how the constraints to the log miner utility can become disabled.  Is there any harm in enabling them even if you do not use this utilty?   This shouldn't affect performance would it?  I wouldn't think it would take up any more space enable as it does disabled would it?  Unless it works like an index which takes up space and memory space if used.  I have never had a reason to use this utility.  We are being asked by auditing about this and need a business reason for keeping them since they are disabled.  I am