You'd be surprised how many people are introduced to learning Perl with an IDE doing a visual debugger run before the actual run.

Once introduced they stick with this habit of having the current line highlighted in their code.

My ex employer was more than unhappy that he couldn't run his web application inside the debugger, and I somehow never told him how to do this ;)

I also think that the introduction of lexical variables changed a lot. Before that action at a distance with global variables created a need for debugger runs with watch expressions.

Edit

But as always, it's not black and white, there are legitimate cases for debugger use.

This DON'T and NEVER rules often lead to dogmatic stupidity.