Shaatra, that may be what her posek told her. Or just what she misunderstood. I learnt long ago that you cannot always just listen to what your elementary/HS/seminary teachers tell you. Ask your Rav as to what you hold.
Remember, socks are a result of moving north. In the desert, they did NOT wear socks. They wore sandals. So many people refuse to acknowledge this, whether or not the rabbonim added it to the rules.