Low traffic is not a reason to ban your account. You should hard work on your Website with SEO to have more traffic.
I have a website which hardly gets any traffic, 1-2 visitors per month and adsense is running fine for it with no issues till date. Yes, but you might not generate lot of revenue if the traffic is low...
I think that the ads should be place on site when you have a good traffic on it and a large user database. Because for a low traffic it have no sense to place the ads but you will not be banned if you do that.