I've been told my out of pocket would be a decent amount before, so I'll hang up and a week later call back and say I don't have insurance I'm going to pay cash

I've been told my out of pocket would be a decent amount before, so I'll hang up and a week later call back and say I don't have insurance I'm going to pay cash and I get better rates. I don't know if it's illegal or not but it has worked for me.