Photo’s that you see on amazon or other websites or print ads with pure white backgrounds are created a few different ways. It really depends on the product that is being photographed as to which way may be the best aka, the most cost efficient while delivering the best result. Backgrounds can be removed in Photoshop, but only done successfully if there are hard edges so the pixels have a defined border. My method for dealing with this is to shoot with a white background that is well lit. After the photos are taken, I digitally select the background that I want pure white and clean it up in Photoshop combining several techniques to deliver a pure, clean and above all, great looking image.