I almost never click on Google links, and I'm sure other people are the same as me and NEVER click/open advertisements. So yes you need lots of traffic and alot of people to click on the lins to just get a few bucks.
If you're after money in adverts look into a company that will pay you annually to post a larger banner on your site. They usually don't do per click, and will pay you up front to just have it on your homepage. Another forum I go to made $900 for 1 year of advertising from a single banner, and a few hundred for another banner.