Reading about HTML::Parser:

As markup and text is recognized, handlers are invoked. The following 
+method is used to set up handlers for different events:
[download]

So I would assume that as long as there are no handlers assigned to those tags they would be ignored.
On the other hand, you might want to define handlers for this code to make your processing life easier.

I'm new to using these tools andh ave never used this one in particular so I'm just stating what I read, someone else could probably provide tested code/answers.

Hope this helps!