In NL every supermarket, baker or other place where you can buy bread will be more than happy to sell you half loaves, to the point that plenty of them have them pre-sliced and packaged ready to go.
I just ask the cashier in the bakery for a half or quarter loaf. Or grab a pre-cut half/quarter one in the supermarket. There are plenty of options (types of bread, sourdough or not, based on different grains, etc) over here in germany.
> This website is of course a non-useful, silly little thing. But I hope that it can get people to start thinking about why more stores don't sell half loaves when it seems like a more practical thing to do.