- Not all search engines can handle JavaScript, Google is leading the way, but not perfect.
- Those NoScript users could be potential clients or users of your site. I love it when my conversation rate goes up 1%, and that becomes harder when you ignore 1-5% of users.
- Screenreaders generally do not support JavaScript [not true, see comment]. If only one blind user gets to access the content/design I created, then that is worth it to me. I am thinking as front-end engineer here, not as a business owner, where time is money. (Also depending on jurisdiction it may be against the law to be inaccessible).
- Noscript users will likely bounce in large numbers when seeing just a blank page. Simply adding a <noscript> tag, explaining why you need JavaScript goes a long way.
As a front-end engineer I go for maximum content accessibility. I don't meddle into the politics of things ("If we don't drop IE6 support, the web won't move forward!").
I totally understand the new landscape, where a lot of people have JavaScript on. Some web apps can not use progressive enhancement, because the JavaScript is core to the app. But for "static" content websites like these, it is certainly possible to make a website that is usable by most users, human and robot.