There are many exceptions to the generally accepted poker rules, especially at Pub type games. There is NOTHING ANYWHERE, that I am aware of that provides for such a practice. That said, there is nothing that prevents establishing a House Rule that permits this practice.
If you do a little investigating, I suspect this came about because at some time in the past there was a player that built up a HUGE stack in the early/middle rounds and then sat back, paying all blinds and antes, waiting for the bubble to burst and to be 'in the money', with out having to risk any appreciable amount of the stack on any given hand. Furthermore, I suspect he/she did this more than once and the rule was put in place as a deterrent to stop this type of thing.
Chet