Why don't I see a path to etags in PATH when running Emacs from http://ift.tt/ocMo9S from the OS X dock?

This is a follow-up question to the one at "Is /usr/bin/etags severely out of date in Yosemite?"

The Emacs in question is from "http://ift.tt/ocMo9S" (GNU Emacs 24.4.1 (x86_64-apple-darwin13.4.0, NS apple-appkit-1265.21) of 2014-10-20 on builder10-9.porkrind.org).

If I start Emacs from the dock, then I don't see in PATH

/Applications/http://ift.tt/1AHSTkq

If I use the script described at "http://ift.tt/1AHSWfO" then I do see the above entries in PATH. But even in this case, "/usr/bin" comes first in PATH. To use the etags found in "/Applications/http://ift.tt/1FkJ36W" I have to give it precedence in some manner. I typically want to run etags in a shell script that is started in the Emacs shell buffer.

Why don't I see these path entries when I start Emacs from the OS X dock (I'm using OS X Yosemite)?

At /Applications/http://ift.tt/1ktBpNB I read:

Emacs.app sticks http://ift.tt/1FkJ3na} on the end of the PATH when it starts, so if we stick our own architecture dependent paths on the end of the PATH then they will override Emacs's paths while not affecting any user paths.