Amazon Groceries and Free Shipping

Tonight I needed to order from Amazon a required reading book for my daughter. The book was $19.95. As anyone who regularly uses Amazon knows, many products are sent with free shipping as long as your order reaches $25 or more. I really didn't want or need to order another book, but I also hated the idea of paying the shipping charge.

What's an Amazon shopper to do?

That's when I remembered that Amazon also sells groceries and other household items. I realized I'd be better off buying something I would eventually need rather than pay the shipping. I decided on a package of razors. The price wasn't any better than I could have done at Walmart or Target, but I loved having it all come to me for free.

I've never shopped Amazon groceries before. Has anyone done a price comparison on things you regularly buy? I'd be interested in hearing a review.