You can refer to more extensive text of documentation with a url to the perldocs. Smaller text is trivial to reformat as needed to put in code tags.
Theoretically the hosting server could use something like Pygmy or similar package to remove all extra whitespace and apply a consistant formatting style to all code tagged blocks..with caching etc. But then that sounds like too much work and testing.
I do agree that the automated line breaks with added plus signs are a bit of an eye-sore. Doesn't help also that you can't TAB indent easily when typing a little code snippet.