Last June 2013 Matt Cutts divulge that Panda and Penguin decreases Google’s revenue and they are still strengthening its updates. Lots of speculations and “Google Conspiracy” thinking drift around forums and other social sites. What do you think the main reason?
Matt Cutts lies. Look at http://investor.google.com/financial/tables.html to see that Google is not losing money and is still growing. You would be better off believing the conspiracies because there probably is more truth to those then what Matt Cutts says.
The truth of the conspiracy is Google wants to make money. Not for you, but for Google. And Google will do what is best. Not for you, but for Google.
Many people ha blamed Google that they are making money by pushing such updates. People would try their Paid Listing (AdWords). Matt Cutts just cleared the confusion that it was not about making more money but the user experience. I think the Google teams ( Google AdWords, Google Adsense, Search Spam etc) don't communicate much before introducing an update or feature. For example, I read on Search Engine Land that Matt Cuts had stated that the websites that will put Ads Above The Fold, might get penalized, the same day I get an email from Adsense Optimization team that I can improve my earnings by more ads above the fold. This is just one example. But I think that will answer you question that the monetization team and search spam team work differently.
The trash sites need to monitize their trash. That is done with advertisements. So if google takes the trash out they won't sell as many ads. But unless they do take the trash out people will stop using google and look elsewhere. So it makes sense to do what they are doing.