If someone with the password wants to share the page it links to then they could just as easily give out the password.
It’s a little bit to stop people from stumbling across it and being given all the details of our wedding. It’s unlikely given the domain name I am looking at using for it but still possible. If someone comes across it looking for something else it’s just another level of security. Yes it’s a weak level but I can’t imagine anyone wanting to get through so bad they would look at the source code. It’s only slightly better than an “enter” button without any sort of password but I’m happy with that.
It’s also because it’s the only way I know how to do it. If I knew an easier way of password protecting the site I’d use that, the more secure the better but it serves its purpose.