Well there's a voice of reason for ya. But, until about 5 months ago, no one even bothered to work that many alternate browsers forthe iphone because of the same reason. I looked, today, and found 2 alternates and 3 in production.
What you're counting on is the "makers" of Mozilla not making Firefox, but that doesn't mean a clone won't be built and that's all that really needs happening before it catches on and then the actual company (or Apple) realizes it will be a benefit to make it. It's all about popularity vs money vs production.
Happened the same way with Firefox for the Mac so don't be too sure of yourself about what's going to happen, it only shows you've either not been on the scene too long or you've got limited thinking on the matter.
After 26 years of watching people say "it won't happen" with software, i've learned a few truisms like being no such thing as bullet-proof security for software.
Plus you're really forgetting Apple's true nature, they tend to "steal" anything that looks really good to advance their look. Someone once said Apple would NEVER do a deal with Microsoft but what happened? Like i said MacOSX is based on a mixture of other OSs and it's killer, Apple didn't make it. They took someone else's idea and tweaked it a little, it's their trademark signature.
"MyFox", an alternate browsers for Safari, is already on Cydia and they will continue to upgrade it so, in a way, you've already been proven wrong.
Dont' count your bets in too soon on Firefox, a "fox" of some kind will come along and bite you for it.