Unique sidebars is something a lot of people want on their sites so they can have different sidebar content depending on the page, post or post type. But an unlimited sidebar function should NEVER be built-into your theme. Imagine you setup all your sidebars then you decide to switch themes…all sidebars, gone!
I highly recommend the WooSidebars plugin for setting up your unlimited sidebars on your site. It’s very easy to use and I haven’t had any issues so far.