The IT benefit to this entire thing is, by enabling this feature, IT will now have a backup of the configuration of all the phones. Even if a user changes a button. Now a phone can die and IT will simply change the MAC on the provisioning server and put the new phone on the desk.
To the business, the benefit is to let users control their own buttons without IT getting involved. Buttons can easily be programmed by a user simply holding it down until the menu pops up. It takes very little instruction to teach users to pick Speed Dial or BLF and enter the number or extension.
For most small shops, this doesn't matter in the first place. They rarely change anything.
But for an organization over 20, it is very common to have users all needing different configurations on their phone buttons. Their Boss, their Queue Pause, their specific parking lots, etc.