I mean, it doesn't make sense to do it any other way. That's half the advantage to selling things in two pieces!
A few of you might remember that I posted a week ago about whether getting a two piece racing/training swimsuit was a good move given how hard it's been for me to find a one-piece that fits comfortably. So now I'm shopping for such a swimsuit, and almost nowhere sells separate bottoms! I've been able to find plenty of separate tops, but damn if it isn't hard to find affordable TYR swimsuits not sold two pieces together. Looking at you, Amazon.