They are dealing with it, just not to the satisfaction of a small minority of the publishers in the program.
Assume that 1 out of 100 websites has been kicked out. I would be willing to bet you that Google could replace the impressions easily. Wether or not the amount advertisers are willing to pay will be affected negatively, I am not so sure about that. For this to happen, the following would have to occur:
1- Adsense provides a lower quality level of visitor than SERPS adwords.
2- The adword advertiser can track the conversion rate of the adsense visitor appart from the overall adword campaign.
3- Enough advertisers notice a discrepancy and decide to act on it by pulling out of content ads.