Very common. Or at least they used to be.

I used to play 5/T at the Mirage, back when the Mirage was THE place to play poker in Vegas.

There were countless racks of those chips in the poker rooms. Since the average buy-in stack was $1,000 - $2,000 in those games, there were easily 500-1000 of those chips on each 5/T table at any one time..