They are the SAME SIZE. Seriously, why do they not fit?

Does anyone have any experience with returns/exchanges at DSW? I bought a pair of black boots online two weeks ago.

I love them. They fit perfectly and are the most comfortable shoes of any kind I've ever worn. I want to marry these boots. One of the reveiws said "I feel like I'm wearing slippers all day" and they are so right. So on Cyber Monday, I decided to buy a pair of the boots in brown. Except they were out of those exact boots, so I bought a very similar pair.

Same size. Same brand. They came today. I excitedly put them on and they were way too small. Painfully small. I checked the size. I wore them for an hour hoping to stretch them out. They were so tight my feet went numb.

I'm wondering if this is a thing with Born? I checked my pair of brown Born flats, which are also pinchy and tight (and bought on some last-chance clearance site so they were non-returnable), and was surprised to discover they're the same size as my black flats, which are very comfortable. Do they use different kinds of leather or something? Am I a different size in brown and black? Weird.

Anyway, DSW will let me return the boots no problem, but I just want a different size. Per their website, they offer "free" exchanges, but that just means you don't pay return shipping or shipping on the new pair (which is very nice). However, the actual exchange consists of a return and an entirely new purchase. I used rewards $ and a Cyber Monday discount on the boots, making them $65 instead of $100. The returns part of their website says when you return something paid for with a rewards certificate, the certificate isn't reissued. It's gone. So what I'm getting from this is if I "exchange" the boots for the next size up they'll credit me my original $65 and charge me $100 for the new pair. Can someone tell me if this is right? I looked for someplace to email a question, but couldn't find anything. I really want a different size for the same money. It looks like you might be able to do this in-store, but I checked and my store doesn't have the boots. Do you have any experience with this? Any ideas?