Maybe because ripple is using the concept of IOU
IOU is a typical way to confuse people and let them fall for the scheme, banks are very good at it. A financially strong person don't need to borrow money, nor lending money, so the concept of IOU only attract those financially weak person. Only banks need IOU, since that will cover the fact that they print money for themselves or they lend customer funds to someone else
When you see the word IOU, you can sense that some scheme is going on here
Call it "escrowed funds" then?
"Bank note" or "balance" might also be correct terms, in the end it is not strictly defined by the network though what your RippleState entries (the internal name for trust lines) reflect - they can be debt, money, time, goods...
All Bitcoin exchanges (even localbitcoins with their escrow system) use strictly IOUs, not "real" Bitcoins by the way.
Fortunately we can have both. It is not a zero-sum game: one person taking ripple seriously does not imply one fewer person taking bitcoin seriously.
Yes it does - Ripple and Bitcoin are in direct competition: every dollar spent on the one cannot be spent on the other.
You need to spend less than one single dollar buying XRP for a few million transactions + reserves, after that you can spend all other dollars for BTC, dogecoin or whatever else you want to buy on Ripple. It's an exchange mostly with an "altcoin" attached to it for denominating fees, not the other way around.
