On afflilate codes, D2D alleges that its links (which can include affiliate codes) will automatically direct customers to the right national store. So does booklinker (which I used to use). So do Vellum store links (which can also include affiliate codes, though that wouldn't do you any good for Amazon codes, which won't earn you anything unless they're clicked from a website). However, I can't personally verify that these claims are true.
Problem is, some of my affiliate links are direct. Those are to the US store. I use D2D
and direct Amazon links on my website (and on independent book pages). The D2D link is linked to the cover. My reasoning is that readers are more likely to click my "Amazon" button then go through the directory under the D2D universal link.
Another thing to consider is that D2D lists Amazon as "Kindle". Believe it or not, outside our writing world, some people don't know that Kindle and Amazon are linked to the same store.
Anyway, the question is, does my US direct affiliate link go to the ISP store? I don't think it does. So now I'm losing money from affiliate links
Don't you love it? The D2D might go intl, like you said, but again, many readers will just click on my Amazon button. So...
Whatever. I give up.