Discussion Forum—A Way with Words, a fun radio show and podcast about language

Brooklyn/Britain - I've been thinking about our tendency to tag an "r" at the end of a word that ends in "a." For example, I remember school friends going out for a slice of "pizzer" (pronounced PETE SIR) or talking about earning their "diplomers" someday. At the other end of the linguistic spectrum, I have been an avid listener of BBC news radio for decades, and I'm always surprised to hear the otherwise eloquent announcers tag an "r" onto words that end with "a" -- but with one difference. They seem only to do so if the word precedes a word that begins with a vowel. For example, they would pronounce "The people in Indier (pronounced IN-DEE-ER) are having an election," or "pizzer is even popular in Mongolia" but they would correctly pronounce "an election was held in India" or "even Mongolians eat pizza." The weird thing to me about this linguistic nuance is that I have only encountered it in two places: highfalutin British speech, and the home-grown speech of my native New York streets.

Does anyone know (a) what this phenomenon is called, (b) if other groups practice this, and (c) is there a cool gee-whiz story behind it?

I've emailed the question to G&B a couple of times but never heard back from them, so I throw it open to you, oh AWWW community, in hope of enlightenment.