I am sure though that we have run into the scenario where we have thought that we no longer need that file and we put it in the the Trash. The whole purpose of the .Trash (even Recycle Bin on Windows) is really a "safety net" since it allows us to go back and restore that file later if we realize that we made a mistake and actually do still need the file.
I know by default that Time Machine does not backup the .Trash folder. So is there a way to force it to include this hidden folder?
That's usually not necessary since the point of Time Machine is to let you go back and view your files. The solution that they would expect you to use is to "Enter the Time Machine" and go grab the file again. This works even if you emptied the trash.
If you did want to backup the Trash, you can go into the Time Machine settings and click the "Show Invisible Items" checkbox. That will let you select the Trash.
The Trash folder is part of the Standard Exclusions for time machine, unless you change the Standard Exclusions.plist, it will not be backed up.
