Backup .rvt Files With Numbered Suffixes

So, REVIT creates backup .rvt files with numbered suffixes in the same folder as the main .rvt working file.

First Impressions:  

This seems confusing at first glance.  When I come in cold into a project folder, there are several .rvt files that are named something very similar. (same name as the working file with a numbered suffix).  

• Why does it make sense to have the backup file with the same extension as the main .rvt file?  

• Do I always select the main file (without the numbered suffix) when I open a file from Windows Explorer?

What Would AutoCAD Do (WWAD)?

In AutoCAD, the backup files (.BAK) are stored in the same folder, but everyone knows you select the .dwg files when you see them in a project drawing folder.  The files are visually differentiated.

Standby for a better understanding...