maybe you thought they were ticklish because you haven't experienced a New England girl? Man I remember one who literally was so ticklish she couldnt' have them touched, at all. She would scream at the top of her lungs.
I've met quite a few SoCal girls. Most of them had tough, thick bottomed feet that were not ticklish at all. They were all beach bunnies, had spent a lot of time outdoors barefoot, and it sucked. Some of the girls were mildly ticklish but nothing I would care about. Finally now I got one who is super ticklish.
I'm a guitarist and I remember when I was young my fingers used to hurt like hell because of the strings cutting into my fingers. Well after about 6 months, it got a little better. Ten years later, I can stick my fingers on a frying pan, they are NUMB. The nerves are dead in those finger tips. Same thing happens with feet. You walk barefoot a lot, your feet lose sensitivity. Sure there are exceptions but as a general rule, its been proven to me. Girls in New England who have their feet protected in shoes for 9 months out of the year are really fun.