Economic stimulus plan

I decided for my first blog to discuss the economic stimulus plan. The bill will issue out about $150 billion in tax rebates for middle-class Americans earning less than $75,000 or less individually. The hope is that everyone will get their $600 and run out and spend it. Many people ask "How will this help, won't it just further the national debt?" There is much truth to this notion, the national debt will increase once again by offering this package. There has also been a lot of criticism toward the president for not increasing food stamp, welfare, or unemployment benefits instead of proposing this stimulus plan. This may be more of a macroeconomics question but where does the government fit in in the market cycle? They give money to households to give to businesses and somehow get back to the government in taxes? This stimulus package seems like more of a quick-fix than anything. Eventually, households will have to pay the money back as national debt begins to diminish. Also, isn't it a bit of a gamble? People may decide to save their money instead of spend which will really not help a struggling economy.

Perhaps I'm just confused, but I'm not alone. Anyone got some helpful information for me?