If you click on the "Email" folder in the Design Studio, you will see the entire list of emails. Within this interface, you can select more than one email and do a mass approval. The only tricky part is that it may be difficult to determine which emails use the template, but if you sort the emails by "Last Updated", you should be able to piece the list together.
But, that's the whole point - to approve only those affected by the snippet update. I am not trying to mass approve all emails.
The emails associated with the snippet may still be spread all over the place after I sort them by Last Updated since there is no information whatsoever of what snippet is used by those emails in the Email folder.
I don't understand why at this point I still have to secondguess which emails I need to approve when it should have been an easy filter of list of emails using a snippet for me to do a one-click approve.
You should be able to see where the snippet is used by clicking on the snippet and then Used By.
I know this doesn't solve it 100%, but you can see which emails to select.