After unchecking the option "Omit badges" from "Instance Options" in the "SC Categories" widget, the number of catalog items that is displayed by Category is incorrect. The number is higher that the one shows in /sc_cat_item_list.do
Any current supported release.
The "Omit badges" option will count ALL active catalog items under the specific category even when "Availability" is set to "Desktop Only".
To avoid this behavior, set the "Active" field to false or, set the "Hide on Service Portal" field to false for the catalog items should not be counted.