Awful, awful decision.
It makes it a tiny, tiny bit easier to buy a headline Apple product for which they create a main website for (possibly, if you happen to be using the website to browse products before you buy, and it's not like a "buy now" link taking you to the relevant store page was hard).
And it makes it a LOT harder to purchase an accessory, non-Apple product, or even a refurbished product.
On that basis, it might make sense for them from a business point of view (after all, they would rather you buy a shiny new product, and you are likely to go somewhere cheaper for accessories anyway). But it makes no sense for consumers.