With privileges come responsibilities.
Falsifying flight time is not the behaviour of a responsible person in my opinion.
As has been said earlier, this is an honour system, but god help you if you transgress and have an incident becasue the teeth of the comb used in the subsequent enquiry are very fine indeed.
Also, don't forget that a pilot falsifying records may well be "shopped" by other members of the flying community if there is a concern about safety etc.