Sharing all bitcoins initially is a very hard (impossible) thing to do. Think about it.
The current method, maybe not perfect, but it *works*. Better something imperfect that works, than some idealistic notion that can never actually be implemented in the real world.
Also consider the nature of bitcoin being peer to peer. You cannot simply "give" everybody a bitcoin. Who's to decide who gets a bitcoin and who doesn't? How is that decision made? The Pope decides? Then it's no longer peer to peer and is controlled or influenced by some person or authority.
I don't think you understand how technically difficult "sharing coins equally" would be. That's the key here: not that everyone would be against the idea, but that it's technically hard/impossible to implement what you suggest in a method that is actually "fair". ("fair" also being subject to opinion)
As it is, it works much like investing in a startup company. It's like we're investing in Apple or Google or something in the early days.
Also you have to understand that the possibility of the early adopters earning a return is a great part of why Bitcoin is now successful. It's successful *because* it allowed early speculators to earn money; they drove its adoption and popularised it. If that had not been so, maybe they wouldn't have bothered so much and bitcoin would have failed or just been a niche curiosity.
The most important thing to know though is that this method is technically simple, very transparent (read: even if it's not considered "fair" by you, at least it's *HONEST* and everyone knows precisely how it occurs, and can easily make the decision whether to use it or not), and also roughly parallel to investing and speculating in something which is widely accepted as a fairly honest method of wealth gaining or creation.
I'm not saying i know well how bitcoins work or convert it to my suggested system. I'm saying a different system should be used where there is an authority maybe, something like paypal, with the proper monitoring to prevent cheating, this has to be thought and invented. each one can open an account and get the coin.
State currencies also not perfect but work. So we are replacing one flawed system with another flawed one?
The bitcoins system looks to me far more complicated to think about and invent than implementing my suggested system.
I think it a new method can be popular anyway even without the early speculators motivation because people should know how bad the current real money system is and will want a fair alternative, and it can be more popular than bitcoins because more people will join if they think they are not discriminated between them and the early joiners.