I think it is impossible that people using bitcoin is only to be used as spending alone or currencies only. of course they will try to get bitcoin or benefit with bitcoin.
I know a lot about the purpose of the users of bitcoin
Yes there are not many options available to spend bitcoin.Not many merchants accept bitcoin.So if you have some coins, investment could be an good choice.It can grow your coins and also help bitcoin economy
How can we help when we are just keeping our bitcoin, I think the only way we can help is to spend our bitcoins to increase the market circulation and everybody will be happy, but like you said we should invest to generate income but to help we should attract others to spend and we take the income.