I'm at work so I haven't been able to read every reply. I'm sure that what I believe has probably already been said but here goes anyway.
Wealth is relative.
What is ' too much wealth'?
I agree with many that have said that giving money to ' poor ' people will solve nothing because if it did work there should be no poverty in any first world country with a social security network.
Wealth is a mindset.
The reason many are poorer than they should be is because they buy themselves luxuries first and try to save or invest second. Many spend way too much on takeaway meals, smoking, drinking,drugs, gambling, clothes - you name it. Try telling a rich guy that became rich by working 100 hours a week for 20 yrs and didn't waste his money on instant gratification that he should give most of his wealth away to a family that eats at mcdonalds most nights because mum is too lazy to cook.
Your post is a good one that proposes a problem that seems to have a very simple solution, but in reality, is a complex issue.
I should add that most first world countries already donate hundreds of millions of dollars to less fortunate countries every year.
I could go on but I have to keep working now :).