Often combining the results of several similar studies can produce conclusions that the individual studies don't support.
VOA: standard.2010.03.25
And even if these studies are flawless and untarnished by the travel industry's stake in the results, their conclusions don't obviate the responsibility to do the right thing for your individual company.
The problem is not that people are being dishonest or falsifying their data (these are practices that are so obviously wrong or immoral that we hope nobody does them), but science requires another level of honesty that goes beyond reporting the results that support our conclusions.