There is harm and I would feel offended if I had donated at the time. If you are comparing the price now, then consider how much potential USD value they have lost with that 50 BTC donation to get a rank that you can now acquire for much lower.
With your way of thinking, there is absolutely no way bitcoin could be anything else than a perpetual store of value, any spending of it would be deemed to be considered a huge loss in the future. And the fact that it would be so defeats its purpose, therefore its value, resulting in a paradox IMHO. I'd be interested reading your way of refuting this paradox.