One really egregious and incredibly frustrating example of a walled garden by Apple is the fact that I can't accept an invitation to view a shared iPhoto librar

One really egregious and incredibly frustrating example of a walled garden by Apple is the fact that I can't accept an invitation to view a shared iPhoto library unless I accept that invitation from Apple Mail. I'm using a Mac, I have iPhoto installed, there's no reason other than consumer-hostile behaviour to not allow me to accept that invite from Gmail in a browser. Hell, make me copy the link and paste it in iPhoto if I need to. Forcing me to use a particular e-mail client is just ridiculous.