Swimsuit Mullet?

So, my friend MelRose is going to vacation to Florida in September. As I was helping her pick out swimsuits, we came across these:

Looks like a normal one-piece in the front....

But turn around, and....

I don't get these. Why would you want a one-piece in the front and a two-piece in the back?!?! Doesn't that defeat the point of both a one-piece and a two-piece? Talk about wierd tan lines!!! Its like a mullet: business in the front, party in the back....