In that case why do controllers ask "...XXX123, say your requested level"?
Is it not annotated on the flight-plan strip?
Yeah, but that's the level filed by the ops folk and not your requested level. And what if they filed a really low level for you due to slot restrictions, but the ATCO can get you higher? That's why he is asking. Just to help you get a smoother flight, or is it because he doesn't want you in his airspace? Can't remember which.