My stack is HTML+CSS
Sure, it's super easy when your page doesn't have even a header and/or a footer. Try having a top-menu in your design, or some banners/ads, and then you need to change ALL the pages to change a single url. This is how we used to do things long time ago, and it sucked BIG TIME, and that's why people invented server-side includes and cgi and mod_php and all of that... it saves time, and your time costs much more than hardware...