1) Bots like to follow the delete link on demostrations and delete all the time-in entries.
2) YBDB adhers to open trust metrics that are common at bicycle collectives, bots really do not care about trust including bots from google, they love exploring every link though.
3) This functionality isn't really necessary since it is possible to make the sign-in time the same as the sign-out time if the person changes their mind about their visit.
Jonathan Rosenbaum