A more plausible explanation was that the cable strain of not using a specialty cable was also an issue. Look at where the cable attaches to the mouse on a conventional mouse - it's usually very reinforced internally or extenernally
Seriously though. This is absolutely correct. I get that some people don't like it, but I really don't get the obsession with the charging port.
I guess I should be glad that these people didn't complain the Apple Watch can't be worn while it's charging.