The only reason mining isn't pure waste for coins like Bitcoin is because it is required to secure the currency.
In Bitcoin there is a fairly clear distinction between the mining done to determine initial distribution and the mining done to synchronize transactions. The first few years are for distribution (with security taking a free ride), after that it's for security.
Bitcoin could have been easily designed so that Satoshi starts with all 21M coins, and hashing is used only for security and paid for by transaction fees. That would definitely cause less resources to be wasted, but it would no longer be a decentralized currency.
There's a tradeoff, the shorter the distribution halflife the less resources are wasted (since the coins are created when they are less valuable) but the less decentralized the currency. If you're worried about the wasted resources, choose a shorter halflife.
Ripple is taking the centralized extreme of this spectrum. If you think about why Satoshi didn't say "I'll assign all the bitcoins to myself, and use them to promote Bitcoin! I'll distribute them to people however I see fit, trust me on this.", you'll understand why we don't think it's a great idea for Ripple.
It's true that Ripple is about more than just the XRP as a currency, but it's a significant part of it and should be treated accordingly.
Essentially, you are arguing that it's better to waste and destroy resources than to use them to promote Ripple. You are arguing that it's better to make people do pointless work to "earn" XRP than give them away for free.
I am arguing that it's better to make people do measurable, algorithmically verifiable pointless work to "earn" XRP than to give a central body built-in authority over a decentralized system.