LOL... of course they can... you do it at the ringing destination level (station, LDN appearance, etc) and not the DDI digits themselves, but sometimes it takes a little "magic" to get things to work. Do you have a specific question on how to do something, or more just an idea of why it was done this way?
BTW, This is the way it was done for a LONG time, from back in the old SX2000 days until MCD 4 (I think) this was the only way to do it.