Mother shooting straw wrapper at my face everytime

I really feel bad when my mother shoots a straw warpper right into my face or chest when out in public.  My mother does not have dementia nor alz.  so far however she was always athletic and sarcastic sometimes when younger. She for the past six years likes to take a straw cover and shoot it either across the room or in my face very hard.  She did this to my father as well who really disliked it and said it was disrespectful. She says in retort "Oh its fun you are no fun." Kind of hard for me as it is humiliating esp. she can do it really hard and usulally it hits me in the eye. Cant seem to get her to stop it at a restaraunt or burger place.  She loves straws and buys them  for home too.  Please help with creative suggestions.  Otherwise she is quite civil in other situations.