"where's the traffic?"
Given that the aircraft commander is ultimately responsible for the safety of his aircraft and passengers, I don't find the request at all offensive. Its all too easy to think of ATC as a real-life video game....there are real people on the other end of the radio!
With sectorisation and procedures in use to-day it is quite likely that some of the conflicting traffic may be on a different freq, and it is not always possible for the pilot to be situation-aware from R/T traffic.....and more so when he/she has just checked in.