FHS , APT policies and *BSD

I wonder why is so hard to install firefox3.1 or pidgin 2.5 on an hardy machine
I have to wait some crazzy dependencies or some broken backports or to give up to previous firefoxes (1.0, 2.0,3.0)

Read how easy it is in BSD

Where the user would immediately begin to notice a difference is in package management. Instead of a large management program, or a repository, users will download a single .pbi file (Firefox3.0.1.pbi, for example). Double-click it, and Firefox will be installed in its own separate directory, such as /Programs/Firefox3.0.1. No mess, no fuss, it just works as it should.
http://distrowatch.com/weekly.php?issue=20080825


I usually when test something new i install it in /opt
so i can have
/opt/firebird2.5.x
/opt/firebird3.x
/opt/firefox3.x