The front door key is the primary level of security for the building and protection of occupants’ property. You certainly don’t want anyone being able to make and distribute copies at random.
If the OP has been able to get copies made, there is a serious lack of security. Respectable locksmiths will not copy security keys without authority from the OC which owns them. The OC/SM should have some records of who has keys.
A few years ago in our block, we experienced a number of thefts from cars and storage cages. We put it down to a departing tenant keeping one of the keys, and coming back to help themselves. We had to fit new locks and have new keys made and issued. The thefts then stopped.