While this is basically true (and even more so for me, typically 3+ months before a security update finally nags me into rebooting 1 month after it was installed) Firefox saves your open tabs, so restarting takes no time and it is basically like it didn't even happen.
You're right (although re-starting firefox isn't quite an instant thing), but like dsr_, I don't turn my computer off - so why would I ever restart a program unless I need to? Killing firefox and restoring the session might not take a long time, but it's always going to take longer than not having to restart it.
