I've been to the Pro store in London a few times, I've never had any deliberate rudeness, but they have been rushed, but then, it's always been real busy when I have gone in there.
In Wales, we have just one counter in Debenhams, and one store that are hardly far apart. In the store there is a guy there who is SO rude. One time I went in, at the beginning of my MAC loving and asked if they did Pro blush palettes and pans. I as fairly new, knew that they were available online and thought they might be in the store, like the shadows. He was so snotty - "Urgh, no, those are only available in the Pro store in London, for pro artists.". He didn't believe me when I told him I'd seen them online. I've seen him at the counter too, although he has yet to serve me again. I am more secure in my MAC knowledge to respond now, I'd probably ask to be served my someone else.
I've been fairly lucky that I haven't had anything too major. But I find the Debenhams counter girls are far more helpful than the store.
My mother though, was treated terribly at the Fenwick in Brent Cross last week. She went in to ask if they had Soiree for me as it was sold out in Wales and online, waited at the til for ages, eventually go the attention of some young boy, who worked for the store I think, and was just putting stock in the drawers. My mum said she knew what she wanted and bless him, he found it. But explained he didn't know how to use the tills, but if she waited there someone would serve her. She waited 20 MINUTES for two MA's to finish chatting (others were all applying makeup) before she finally ame over and served. Utter rudeness and then she had the cheek to be all "Hi honeeeeeey, what can I do babe!?". My mother was not impressed, and told her so.
Why busy ounters don't have one allocated person to ring up purchases I will never know, you can get some student or young 'un who doesn't know squat about makeup to do that on busy days.