Are MPs right to appeal for a re-instatement of Google’s gambling ad ban?

The debate surrounding the changes in Google's gambling ad policy continues in full force with the news that MP's are calling for the re-instatement of the ban on gambling ads across the search engine. By overturning the policy in the first place, Google was clearly responding directly to the credit crisis. With advertisers dramatically cutting spend or pulling out completely, Google needed to fill the hole in its revenue fast. So far the change in strategy has proven effective, with the average cost-per-click increasing from £2.50 to £15-20 three months on. We've estimated that the annual turnover from the gambling sector could easily reach £300million, if not more, should the bidding war continue. These estimates seem pretty accurate, especially with the affiliates getting a look in now. Having said that, I don't necessarily agree that Google needs to review its policy in line with its own obligations on corporate social responsibility, as requested by the MP's. In fact, I would say that the responsibility lies with the gambling companies themselves. If they are allowed to advertise through other channels such as television; then why not through Google. Google's overturn isn't a free for all; there are regulations in place including an emphasis on gambleware. Therefore, shouldn't the government encourage and assist Google in monitoring the gambling companies, as opposed to calling for a reinstatement of the ban?