I'm sure they have fun in their own way, like which curling irons are the best to retain a curl and what hair styles are best for straight hair....or even just regular maintenance on what products to use to have healthy hair ect.
Most of my family on my dads side have straight hair, one of my cousins can't even use conditioner on her hair! She says it gets oily too fast and conditioners weigh it down so she shampoos everyday!! With sulfates!! and her hair dries straight, silky and shiny. She loves my hair though and wishes her hair could hold a curl.
They may have their own straight hair forum secret society...who knows.