My mother who is an ESTJ is prone to this? She has the ability to keep mental snapshots of what people look like, so if she hasn't seen them for a length of time, she can notice if they've gained or lost any weight. If I gain any, she'll be the first to say, "Well your jeans are looking a little tight. Someone needs to take the dog out for longer walks!" My brother's long-term girlfriend has gained quite a few pounds, and my mum drops hints like, "Maybe you should join a gym?"
I would have thought that while STP types have good observational skills, their Fe would keep them from saying anything, out of politeness. STJ and SFP types have Fi; "sometimes things just have to be said." So, maybe ESFP types are the most prone, out of the SPs?