Why is Pinkberry so popular?

I had Pinkberry frozen yogurt for the first time at work. A coworker didn't want one that someone had brought for him so he gave it to me. I thought it was just OK but I chalked it up to the fact that I hadn't chosen the flavor or the toppings. Today, I had Pinkberry again. It is weirdly tart and thin. Why does it have to be so weird? Why can't it just be normal?