[jrumbut]

I'm not defending the sigils because they are terrible, but the reason you can't just get rid of them is that they are actually used.

For instance:

my @arr = ("Larry", "Moe", "Curly");

my $len = @arr;

will store 3 in $len. Application codebases and libraries make use of this kind of thing everywhere.

You can find some of the reasoning why in interesting essays like this: http://www.wall.org/~larry/natural.html

Larry Wall was trying to incorporate some natural language features in Perl, unsuccessfully in this case but I would say it went very well in others.