Roberts calls it Pavlovian because he conceives of a specific flavor as an unconditioned stimulus and calories as the conditioned stimulus. He thinks set point changes are a response to a learned association between calories and a specific flavor. It's not a perfect fit to classical conditioning, but it's not a totally wacky naming. (I agree that PCT is a better fit, but it seems unlikely that Roberts is aware of PCT.)

Indeed. I'm pretty sure the word "Pavlovian" made its way in there mostly because the revelation involved salivating.