Does hoarding really hurt Bitcoin?
Nope. Everyone is free to hoard. It's really stupid when people claim "if you just hoard it, and don't transact it, you are hurting bitcoin!". What the hell is this logic? It is my bitcoin, I do whatever I want with it. If I choose to hoard it then so be it. It is stupid to spend your high quality money that appreciates with time when you have bad quality money that depreciates with time (fiat) to spend things you can already buy with it. Hold the bitcoin, dump the fiat, that is what the intelligent people do. There's no point in doing payments in bitcoin unless you really need to (like paying an VPN service for example.)
For some people with big amount of bitcoin, it maybe yes due to they can dump bitcoin price instantly after some sell strikes within hours.
Consider how many bitcoins generated everyday;
As of the latest block reward halving on 9th of July 2016 each block now generates 12.5 new bitcoins. On average a block should be mined each 10 minutes but, because of the constant growth of hashing power (at least until now) each block takes close to 9 min on average to be mined. That means we mine, on average between 1440/10*12.5 and 1440/9*12.5 so between 1800 and 2000 per day.Miners could generate so many bitcoins in a day, and the big whales of this crypto world are the miners with mining pools.
They have to sell bitcoin everyday to cover their daily expenses, in that case, bitcoin distribute among the holders, investors or traders.
Fortunately, most people can't wait to extract profits by selling their bitcoins which make it distributed and spread widely, instead of just hoarding.