Why no filter for text areas?

Hello. I was doing some form validation today and I noticed that
there's no filter for text areas. The :input filter includes it
but :text excludes it and it doesn't have a filter of it's own.
Personally I think that :text should include text areas and barring
that, there should be a filter for text areas just like for all the
other big form input categories.
Kindly, Marcus.