1) There will be zero forge income for people just buying NXT because it is great platform?
2) How should look real example of successfully forging individual?
As far as i understood it, people will buy it because:
1st:
That is my understanding, too. And CfB said something similar also, I think (coins for currency, NXT for value)
NXT itself is backed by power to influence on the whole system. If u own 1M NXT then u'll forge each 1000th block. And u can charge fiat money for inclusion transactions into blocks.
I'd like to add that this "power" is very valuable. If u forge the next block u decide what orders to include into it. And this decision will change the market.
NXT -> Power -> Ability to change the world2nd:
They will buy it to exchange it for coins backed buy Nxt and use those coins as a means of exchange
3rd:
Business in the Nxt ecosystem will buy and forge it to support the network which serves their businesses