I've seen lot's of people who complain to bounty hunters who dump their tokens after they get them. Why hate them? They have all the rights to sell whenever they want and bounty allocations are only 1%-5% of the total supply of the coin. I don't think it will do much to lower the price of the coin. I mean it's even good for the ICO investors as they will have a chance to buy more tokens with lesser price than the ICO.
Holding the tokens also doesn't mean it will make you rich. Some tokens get abandon by the developers so it would be better to sell at a good price than be left hanging in the end.
When new coins list there is usually very little liquidity and not many people buying. This means that it really doesn't take much to drop the price significantly. I think the reason many people have an issue with it is that bounty hunters have zero risk. They haven't put their money on the line by investing and have lost nothing but a small amount of time if the price tanks.
That being said, many ICOs don't get many investors these days anyway so I personally don't have much problem with it. It might actually come round and bite the bounty dumpers in the end if the coin decides to grow exponentially in the future.