If a disk drive is the folder selected for loading into Mp3tag, audio files in the recycle bin are included.
For example: if "Change directory..." 
is clicked and (W:) is selected, then all audio files are loaded, including those in the W drive's recycle bin.
As far as I can tell, the only thing Mp3tag allows for the files in the bin is "Remove".
It is probably inconvenient to reproduce by anyone with a large number of files on a every hard disk.
I discovered it by accident when using a "work" disk that had less than 2000 files.
This is not much of a problem, but it seems like undesired behaviour.