It is abuse of a glitch that SA:MP did not block in their programming.
How it is handled is depending on the people present and the situation.
If no admins notice but a police officer does, a suspect for stealing government property is allowed.
If admins notice they can : warn, kick, or ban based on the player and how he reacts.
My first action in such cases is to disarm, if the player lose other weapons he bought because of it he will think twoce before stealing again...