Do dogs really want to please us?

I don't think so. I don't believe they are altruistic at all. Say you're sick, or sad, and your dog becomes more affectionate, stays with you, seems solicitous. I don't believe the dog "feels sorry for you." Maybe he wants you to feel better because if a pack member is out of sorts, pack balance is upset and this isn't the natural order of things? I doubt Fido is thinking "awww, she feels bad and if I stay close by and nuzzle her hand, she will feel better." That doesn't seem right; I think that's putting human emotions on an animal.
Maybe he's staying close because he is hoping you'll die and he'll then have a very large meal, so he's thinking he needs to hang around to keep his eye on this potential, very large meal. Haha. (Actually, this may not be too far fetched. Your dog is an animal, not a little furry baby! Have I ever mentioned I hate the term "furbaby"? Yuck.)
At any rate. I wrote on Sunday, about Cooper's recent unwillingness to go up and over the dog walk. He'd fallen off, and lost his confidence; we have trials coming up and he needs to be confident and sure-footed (and safe) on all the equipment.
I just love this dog. We worked on it at Tuesday night's class. He was really conflicted - kept starting up the thing, then stopping. Coop is an incredibly confident and macho animal. If he's nervous about something, there's a darn good reason. Coaxing made it worse - almost seemed that it had to come from within, for him. (Am I anthropomorphising? I'm not sure.)
I decided not to push the issue too much, and we did some little run-throughs on other equipment, so he could relax and have fun. Suddenly, and without bidding, he ran over to it, started up, got nervous and hunkered down, than crawled across on his belly. Why? It scared him, I hadn't asked him to, but he did it anyway. Of course he got big praise, so he did it again. I wasn't asking him to - he was offering the behaviour. Awesome!
By the end of the evening he was confident and strutting over the thing, pleased as punch and proud of himself.
So, did he do this to "please" me? I don't think so, I think it was something HE wanted to do. My dog-savvy friend Erica was over last night. We decided that maybe centuries of work ethic instilled in certain breeds gives some dogs an innate desire to do something correctly for their own satisfaction. He knows it's a job, jobs must be performed properly and that is just the way it is.
Of course this isn't as ingrained as pure animal instinct. I am guessing even the most seasoned and enthusiastic agility dog wouldn't bother with any of the equipment if they were let loose on a course in absence of humans.
Did I mention I just love this dog? He has heart and work ethic and drive. I wish I was a better handler, but we muddle through and have fun.