No, not at all. I view it similar to the classic Dropbox discussion. There were existing alternatives, but Dropbox took off because "it just worked" without having to use FTP and Linux. In this case, you eliminate the VPN step, by linking the router to your devices and using that single device to connect.
Secondly, with VPN, I first have to connect to the open network in order to activate the VPN. I also need to do it for each device I want to connect (phone, computer, tablet).