Last September was my first time discovery of foot mask while I was in Hong Kong. The tour leader introduced it to me. (i know i'm kinda out dated) I seldom see it in the market until I was in Singapore in December. Sasa store had them and I bought 2.
So far I only can find it in Watsons' store in Ipoh. I didn't find this useful unless I'm traveling. It's not moisture enough for me and it's expensive. Buy in singapore cheaper... hehehe