Bad service at Barneys New York. Is it rude or not? Please advise.

I don't think you've said anything inappropriate at all. If anything, I think you'r e too kind and by the looks of it, too easy on him. You need to report him asap. Being that it is retail, I think the chances of him getting into trouble with his manager are very likely. Sales people can be fired pretty easily (most of the time) from what I've seen.
 
I don't need/want SA's fawning over me but that would've p*ssed me off, big time. Doesn't matter that it was a high-end store or that you're returning something. That was just really poor service. I don't know what it is about Barneys, I was at the BH store last week and in the space of the size of my (not large) living room there were 3 SAs, NONE of whom helped me even though I spent time perusing the bags, trying them on, etc etc.

Contrast that with Bloomie's, I stopped by there on the way back from the gym (!) to return something and the SA treated me like I was a celebrity, offered to presell the jacket I was buying, gave me her card, sent me off with a smile even though I was totally grubbing it in my sneakers and baseball cap!
 
My experience with Barney's in-the-store customer service has always been good; however, their credit services is a nightmare!

They sent me a credit card, which was arrived 35 days after the account was opened, which prevented me from setting up my online banking with them. They refused to give me my account number on the phone but were more than willing to take my bank account info over the phone.

I sent them a payment via mail two weeks before payment was due. They said it never arrived. I cancelled the check, paid them in full and promptly closed my account. Think LONG and HARD before opening a credit line account with them.