THis is right too!
I said, because in my games, of course, I see many times, the computers changing its route, to use my roads, because, I did some better (short, I guess) route!! in this case, would be very interesting to have this little tool to receive some extra money. OF COURSE it wouldn't be enough too be rich, but this can be an option for users, change their rent values, understand me?? And in a competition game, we have to be over your oponents, because you need do more money for you, if possible, winning its bussiness. Its' a wild world.

lol
But there are many styles for play, from greed/ambicious++

style until pacific and happy guy style.
In this (ambicious killer mode) you can make the oponents life a hell, doing concurrency in all bussiness that he owns, just to reduce his receips, right.
in the pacific mode, you can just stay away of oponents being the one that do some kind of work for some cities, grow up this way by time.
Anyway, coukd be simple, but could be better. Depends of player and his strategy to make money.
I didn't think in all Scenarios yet, of course,this can done be here with your opinion, right!
Like belungas mentioned, I have too, a favorite kind of game, and I have to find the game that fits in my preference, and not change it to fit in my opinion. But if this was a rule, or even a better advise to follow, so why the TTD gamers decided to make a new "version" of the original TTD, changing things, fix others, etc.
I beleave, that one reason was there weren't games that fits in the needs of this gamers, right. So they decided to do they own version with they opinions of what, how and why should be in the game or not, try to following a "logical line".
I think this same way. I prefer games that are simulations of reality, could have some fantasy of course, but if it has major things based or like belungas said INSPIRED in real things, i think that other parts of game will "fit better" if would be like reality too. I don't wanna be boring with this. It's just want to explain my point of view, understand me?
By the way, thaks for the tips about airports, I will check.
Thanks guys!!