And your tongue touches your lips often, thus you get to experience the taste without actually consuming a substantial portion of the wax. Compare this to putting the same stick in your mouth and eating it – the wax would coat your entire mouth quickly, so you’d be feeling the slimeyness much more than tasting anything. Since scent is a portion of taste, I would theorize that the wax coating would prevent air from combining with the artificial flavour, so you may not even be able to taste it after your mouth is entirely coated.