From a behind the bar point of view, every now and then Ill get the occasional request for a HOT coffee. An I have no problem bringing the milk to the limit for them; however, if they dont ask, then I wont know. On average, I tend to not push the milk too far past what I believe is optimal temperature for milk as my cups are pre-heated quite nicely.
I personally wouldnt feel cut if you asked for it to be hotter than youve gotten it, whether from another shop or my own. Each customer is different, and expecting them to be all lemmings would see a loss for me. Speak up, just be civil.