I worked for Delta Faucet (Jackson, Tn factory) making faucets on the assembly line about 18 years ago. The only difference between Home Depot/Lowes faucets and what you get from plumbers supply is packaging and sometimes the hookups. Back then the ones that went to Home Depot/Lowes had connections for screw on hoses and the ones that went to plumbing supply places had straight pipes that had to be soldered. Otherwise all the internal parts were exactly the same. Delta also makes Peerless faucets. The main difference between Delta and Peerless were the escutcheon (that's the base plate), handles, and the warranty. Otherwise, all internal parts were the same. As for the warranty, Delta has a limited lifetime for the chrome plating and Peerless had a 5-year on the chrome (if I remember correctly).
Again - this was 18 years ago. I cannot testify to the accuracy of this information today.
That said - we had to replace the faucet in the house we bought in 2013 and got a Delta. The parts look like the same ones I assembled 18 years ago and we have liked the model we purchased.