I am curious how you reconcile these statements.
If someone starts a topic "Why pick PF?", you say you will make the case for PF.
But then you say you're not interested in evangelizing Pathfinder, and that you don't see a reason to bother unless you are recruiting for your local game, and that games have already been selected.
So, I am guessing you see a difference between making a case for PF, and other people making a case for the game they prefer. I am not seeing a difference though, and I suspect whatever you're feeling that makes you want to post a case for PF, is the same others are feeling when they make a post in favor of the game they like.
Your guesses are incorrect.
The distinction I am drawing is between someone asking:
A. "Why play Game X?"
(i.e. Someone is asking for feedback about what other players find appealing about the game."
vs.
B."You no longer play Game X. What would make you come back to Game X?"
(i.e. Someone is asking how the current edition would need to change in order for the "lapsed" player to return.)
as opposed to:
C. "What would <#> Edition of Game X have to be like for your to come back?"
(i.e. Someone asking what mechanics or other factors would have to change to "return the customer to the fold")
A is merely seeking info about a game from fans of that game. C is brainstorming/fantasizing/polling for data regarding a future edition.
B is seeking to bring a player back when (presumably) all the things that caused the player to leave in the first place are still intact. If a publisher is asking that question, it makes sense -- they want the customer back. For the anonymous gamer who won't make a dime or add a player to their table seems odd to me, hence the "why do you care" part of the question.
That I happened to make this observation with regards to 4e was coincidental. If I'd noticed a lot of "Pathfinder recruiting" or "Traveller recruiting", the thread title would have read "PF/Paizo:..." or "Traveller/Mongoose..."