i wouldn't be rude about it, but i wouldn't give lengthy explainations either.

with the number of ups guys tortured by dogs, you can imagine them trying to make their jobs easier, and for many dogs, a cookie will make him coming better for everyone.....

just say "hey, i am doing some pretty high level training with my dog, and part of that is treat refusal. would you mind not giving mine any more treats until training is complete? thanks"

leave it at that. going into your dog being a ppd will often translate to them at least as attack dog, or guard dog, and they might just become afraid of your dog, which is not good either....

maybe after you have gone further in the training, you can ask him to occasionally bring treats(you watching from a distance), to see how the dog does "alone".

Or, just put a sign in the yard that says "Don't Feed The Dog".

I do on site computer repair so I end up at a lot of houses where people have dogs. I can fully understand why the UPS guy would feed dogs on his route. A "Pleas Do Not Feed" Sign however should be clear enough to get the point across.

Actually to tell the truth I've never had a problem with any dogs I met even the ones the owners say are aggressive. I just stand still and let the dog get to know me then go on up to the door. I've even had people act surprised that I got past the dog without trouble.

For myself, I'm not of the mind that I have to or should have to be putting signs up that I also have to live with.
As I said previously, the dog is not an issue for anyone wanting to come to the door, the meter, the fuel tank, or for that matter to wander around the property. She is always with me or kenneled.
Mallory brought up a good point I did not bother to write out, so I will now, before everyone thinks I some kind of real SOB. I do say face to face with the offender, 'thanks, but I would rather you not feed my dog' the first time. If it happens agains, I become more forceful with, 'PLEASE do not fed the dog'. If it continues the home office gets a call and dispatch is notified and I have no more feeding problems from that company.
Up til my last dog I never really gave it a second thought. But she was allergic to wheat in any form, and basicly I got tired of giving explainations. Then one day I realized I don't need to explain a thing. I don't need any reasons or excuses. I just plain don't want anybody giving my dog something she doesn't need and I don't want her to have. So stop it.

It's that simple.
Randy

I agree with Susan. It's always better, or at least more productive to try to enlist the help of the UPS guy/gal then to alienate him/her. I'm sure their intentions are good, just misdirected.

 Quote: John Stopps

Every time the UPS guy comes, my wife says that she sees him give the dog a biscuit, which he gladly takes. Has anyone else seen them do that?

You obviously never were on Lloyd B's route. He carried milk bones in his shirt pocket and trained the dogs on his route to jump up on his belly and chest to get a biscuit.
I can't say what the owners thought of this but I do know that the UPS supervisor who rode with him occasionally was not pleased when the dogs gave him the Lloyd greeting, muddy feet and all.
Back when I cleaned the UPS trucks there were only 2-4 drivers out of 40 who kept a box of milk bones in the trucks, so at least in my part of the state treating dogs on the route was not the norm.

It's a pretty common tactic for UPS and the mail man in our rural district to throw a dog biscuit for a dog. Really on their side of it if by giving out a milk bone they can keep the dog distracted enough that they don't have to interact with it further (aka possibly be a chew toy for a random dog) I understand why. I've done ride alongs with enough postmen that it's amazing how many aggressive underexercised dogs are left alone in front yards with no way for the postman to get to the door without opening a gate or passing through a bite zone.

My personal tactic is to have a good relationship with the UPS, Fedex, USPS, and DHL guy (yes I know their names... and I'm pretty sure their dog's names too) and set them up in situations where they won't have to interact with my dogs to get to my door/porch. If they do interact like while I sign something I keep my dogs politely sitting. If the delivery guy offers a dog bone I thank them and politely say no, I don't feed milkbones.

Really I think you can just talk to them and get the issue fixed.

Yeah don't offend the UPS guy or he might spit on your packages.

These guys probably think they are being nice giving the treats. Around where I live most people wouldn't have a clue about not giving a treat to a dog that they see on their routes daily. Even the banks in my area gives out treats to the dogs through the drive thru window and the fast food places gives them out. Even the frozen custard place gives a "baby cone" sample to us for our puppy (which my husband eats as soon as we drive away), so I wouldn't be rude, I'd just let them know that you don't want your dog fed treats. (think about how people use to give candy or suckers to kids without asking parent approval). it's just an example of people not knowing.