Sharing a File via Outlook.com only Shares a Link and Doesn’t Share to Person

I've noticed when sharing a file with other people on SkyDrive via an Outlook.com email, it sends a view or edit link to the recipients. Why doesn't it automatically change the share from a link to specifically share to that persons account when the recipients have Outlook.com addresses or Microsoft accounts? If I send an email that shares a link with someone who does have a Microsoft account, it would be nice if it converted that to a specific share to their account as well. Are there technical or logical limitations to that?