Mouths seem to be more sensitive than hands.
A cup of Starbucks chai or coffee that's too hot to hold is usually just the right temperature to drink. If it's not too hot to hold, this indicates that it's only lukewarm, which is really icky and undrinkable. It usually does need to be somewhat hot. However, I always drink Dunkin' Donuts coffee. They serve it in a single cup and the temperature is fine, so I agree, I'm not sure what the deal is with Starbucks.