Store Locator Plus adds the ability to select categories of locations using checkboxes with the Premier add on and Power add on installed.
For WordPress plugin users, you will need an active Premier Subscription to enable the new feature. It will also require SLP, Power, and Premier to be updated to version 4.8.4 or higher.
MySLP Enterprise level users will be getting these updates in the 17.10 upgrade to the service later this month.