I believe the point is some of us have aspirations for a society that minimizes the number of people in terrible situations. The idea being that some of us feel many of these terrible choices are as much the result of circumstance as otherwise.
Particularly for someone like me who doesn't believe in immigration control at all, deportation (or even subjecting someone to the horrible abuses of ICE without actual deportation occurring) constitutes a cruel and unusual punishment for a crime that should be punished by a fine or a few days in jail.
If I knew a drunken bicycle thief-citizen would be imprisoned for years, I wouldn't report them, either.