In all the years that I have used Joomla I have never really seen the need for front end editing. Why bother? I could just do everything in the admin.
There were always too many things that I couldn't do on the front end that meant I was forever switching between the two.
Editing your site can be hard
I get it that people don't want to be bothered with the complex interface of the administrator and prefer to edit their content in place. This has been possible for a very long time in Joomla for content items but not for modules. So you still needed to switch to the admin interface to edit them.
On a complex site managing your modules can be a real pain. How many times have you edited a module and not seen any change only to realise it was the wrong instance of the module. You ideally need to see the module where it is used in the site and select it for editing.
Joomla 3.3. Changed that
Since Joomla 3.3 there has been an option for administrator to do exactly that. Hover over the module and you will see an edit icon. Click on the icon and you are taken to to the administrator interface to make your edits. This is great but you still end up having to deal with the complex admin interface AND it isn't consistent with the way you can directly edit content.
Joomla 3.4 Takes it to the next level
With the upcoming release of Joomla 3.4 this is all going to change. The edit icon is still there on the screen for people with the right editing privileges BUT instead of that icon launching the admin you can edit the module, any module, directly.
With Joomla 3.4 Editing modules is faster and easier
The Old Way
The New Way