I asked the girl at PetSmart once what her carbonate hardness was at
home (KH) because mine was so low and I wondered if she had problems.
She told me she didn't know what carbonate hardness or buffering
capacity meant. I explained it to her but in my head I was thinking...
"Geeze lady, you sell fish in a city where the KH is less then 30ppm.
It's obviously an issue you NEED to know about."

Some people don't know enough about the hobby to even be a liar.