Why in the world would any one feel it's OK to use cuss words when having a casual, non-confrontational conversation with a complete stranger?

I was at Goodwill today. A woman was looking at a coffee maker. She asks the clerk, “You guys check your shit out before you put it out on the floor, right?”

Later I heard a sound that mimicked the “beep, beep, whawwww” of national broadcast emergency testing. Then a woman’s voice came on the “radio” and said something about a severe weather advisory so I tuned in….and the the woman’s voice said “It’s gonna be a hot motherfucker today!” I looked up and it was that SAME lady, standing in the middle of the store, phone on speaker, held up for everyone to hear. It was some sort of cell phone joke. Ha ha. If I’d had one of my little ones with me I would probably have said something to her.

What is going through people’s heads sometimes???