Why do I keep getting yelled at for wearing a cross?

I wear these two pendant all the time (one is the cross of st. peter and the other is a satanic cross.) well i can see Christians getting mad at the second one, but they all seem to yell at me about the first, which is a catholic symbol. The reason i wear it is because it belonged to my deceased grandfather, and even though I’m not Christian it hold sentimental value, so i keep it on me. I was in Walmart the other day (I usually don’t go in there, this was a special case) and some random lady started yelling at me about the upside-down cross. she was saying all sorts of stuff and causing a major scene. needless to say i was disgusted and pointed out the ACTUAL satanic cross (which is much more visible, its on a shorter chain) and walked away. It was super embarrassing and slightly offensive to have some random lady start yelling at me about my religious choices in a public place, I just want to know why Christians can wear their symbols around but for some reason I can’t. Its not like i wear it to attract attention or to start arguments its just a habit I’ve gotten into and i don’t feel like changing. its also not like my necklaces are huge and gaudy and attract attention either. I guess i want to know why so many strangers feel the need to insult me.