Is this sarcastic?

Hello.

I had a chat with a customer service rep on a very well known website this morning, after which the rep followed up with an email that started

“I am grateful for that kind and warm approach you gave on the chat. It is indeed a pleasure helping you out today.”

I wasn’t rude, just straight, I pleased and thank you’d regularly throughout but I don’t have time for the inevitable small talk so I usually slide past it.

when I challenged it with another advisor they claimed it was one of their standard responses, which i highly doubt, and closed the conversation. 

I am still shaking and it was hours ago.