That is not quite the correct version of the story. Bhoomadevi doesnt complain about the burden of population. If that were so, then consider the population now! It is much much more than what would have been during the Dwapara age. And also consider how many people died in the war! One tsunami that came last year destroyed more lives!
It is all absurd to say Krishna came to destroy the population. If that were the case, then every criminal who is accused of genocide is an avatar! Even Hitler, one can then argue, came to reduce Boobharam!! What Bhoomadevi complained to Krishna was about the load of Adharma. The earth is carrying mountains and oceans! Is the weight of puny humans going to be unbearable? It was the weight of adharma that she is said to have lamented against, and which was the reason why Krishna declares too that "Yada yada hi dharmasya glanir bhavati bharatha" etc.
To not recognize this fundamental fact and to merely look at the superficial meaning only shows the entire epic and the sacred avatar of Krishna in a bad light.
I know that was most certainly not your intention, still, I thought it is really necessary for us to understand the real meanings behind the epics. So, please do not take this personally, Balaji.