I see what you mean! It's certainly not the end of the world, but you obviously want a white background and you should be able to have it. Have you tried Fotofuze ? It's a site where you can easily make your backgrounds white (or black). You upload your photos to the site, make the quick adjustments and then save them to your computer (or device). It's quite quick and very easy. The help page, or video will show you how to do it. It's a really useful site.
The site has a free version and a paid version. They work exactly the same, but the free version will reduce the size of your photos (can't remember the size, but still quite acceptable). Having the reduced size hasn't affected my sales at all as buyers can still see from the photos what they are buying.
