Quick way to delete a theme

Some functionality seemed to have disappeared with V3.8.1

The ability to delete a theme from the themes menu, (wp-admin/themes.php) Now you have to click on the theme let it load and then delete it. This is very tedious when you have a lot of themes to delete.

I would like to see a Delete button next to the Activate button and better still the ability to select multiple themes and delete them (the way you can with plugins)

Many hosting providers now include 50 plus themes when they install WordPress.

I have tried deleting these via FTP but WordPress gets confused and still thinks they are installed.

Is there a quick way to delete themes, no point having so many themes installed, they waste backup space and some could pose a security risk (tim thumb).