Bend in Mixte seat stay..as designed?

I looked at a Miyata 100 mixte today, and decided not to buy it because there was a bend in the seats stay on the drive side. As I drove home, I wondered how it could have happened, and then I wondered, was it "as designed"?

The stay was curved out a couple of cm's between the seatpost and the dropout on the drive side. The other stay seemed straight, and the wheel seemed centered. I can't think how the bend could have occured: a bend in, yes, but out? Where would the impact have come from? At a glance, the wheel appeared centered on the chainstay.

Also, I wasn't sure what effect such a bend would have in any case. Was I wrong to turn it down?

Any thoughts?

Here's a pic: