Microsoft Stores actually had a policy that the PCs they sold were only allowed to have clean OS images ("Signature Edition" was the branding term), which means that it was the safest place to buy Lenovo/Dell/etc. You'd pay on average about $50 more than if you bought directly from Lenovo or Dell, but you'd have peace of mind that you wouldn't need to reinstall Windows to make sure that you had removed all the spyware/adware.
ETA: Which is maybe the biggest loss with the Microsoft Stores going away. You could point a relative at a Microsoft Store and not worry about any PC they picked, but any other store you'd need to expect to do a reinstall for them or worry about which specific brand name they picked.
ETA: Which is maybe the biggest loss with the Microsoft Stores going away. You could point a relative at a Microsoft Store and not worry about any PC they picked, but any other store you'd need to expect to do a reinstall for them or worry about which specific brand name they picked.