Underwear doesn't count as a swimsuit. Especially your kind of underwear. And your children are definitely too old to be running around butt naked in public. I thoroughly enjoyed watching your families spend the day at the beach doing all sorts of weird things and wanted to take pictures of you, but realized this might have seemed a little bit creepy.
Subtext: I went on a day trip down to Santa Cruz on Friday and enjoyed some sun, sand, ocean, and some pretty weird people. In addition to the beautiful view of the ocean I had from my spot in the picture below, I also watched old bearded Indian men meditate and light all sorts of funky smelling incense while chanting. All in all, I can't wait to go back to the beach again soon!