There is nothing wrong with running UF in a raceway if it is big enough. I suppose it is just what they have on the truck.
HVAC guys usually end up using bigger wire than they have to for that reason, although I doubt most really understand the ramifications of the nameplate rating and the break you can exploit from that. I also see ECs using bigger wire than they need on the line side of the disco but that may be because they don't get to see the actual condenser until it drops ... the day before the closing ... just to be sure it doesn't walk away.
