Disney Plus service is now up, but unfortunately the Donald Duck cartoon, The Clock Watcher isn't available for Disney Streaming, that answer may change once this cartoon short is on Disney Streaming.
It's unknown why the boss hired Donald Duck who was the worst gift wrapper in the store department. It could be that no one else wanted to work wrapping gifts or that the boss didn't want to have to pay for more people. The boss does mention workers in the store, however they could've been in the sales area or were taking time off for vacation.
You can find it on DVD in The Chronological Donald Volume 2 or you can find it on Classic Cartoon Favorites : Volume 8 : Holiday Celebration with Mickey and Pals. Or you can watch it at youtube.com or dailymotion.com