I am just examining AppZapper now. It is true that if one knows what app one wants to delete, a quick search in Spotlight, (or better, the freeware Spotlaser,) will yield all the related files one needs to trash.
But AppZapper will also list all of your apps and how long since you used them; (press the Genie's lamp icon.) I was amazed as to how many apps I have simply carried over from computer to computer.
So, AppZapper may have use as a means to get rid of those Apps that have not been opened in two years.