Why Secure Your Entire Site? When you view a webpage, that information passes through a dozen or more servers to get to you. If that URL starts with https://, anyone in the path can view or even modify the contents of the page. ISPs insert their own ads in web pages, can now legally track & sell your browsing history, and many governments around the world collect massive troves of browsing data. Securing your entire site (instead of just the checkout portion) is now considered a very good thing to do for your users. It's nearly impossible for a 'man in the middle' to extract or change information on secure pages. It's a win for the user. Here is a more detailed explanation of HTTP vs HTTPS (https://ahrefs.com/blog/http-vs-https-for-seo/) if you want more background.