i don't think this is a greedy behavior because some of people want to hold it until another folk coming
and some people is a true fans in bitcoin ,
Yes , people end up acring like that because Bitcoin is very unreachable nowadays, it may be impossible for them to get some in short period of time cause the people know this were increasing day by day.
Holding is you can say greedy but the fact is you need to be greedy for having some good amount of money. At the very present time, holding is the best way of making money and it will for sure help you in makingsome handsome amount of money as the market price of bitcoin is rising very much significantly in no time. The only thing you need to have for that is controlling your emotions under your control.