What are you talking about?
It just might be true that investors bought property on speculation that they would earn money through the eventual sale at a higher price.
It may be true that some of those folks bought more than one property with the same intention.
Further, it might be true that it was better financially for them to look at short sale theories for disposal of the property when the market fell.
It could be true that this caused amplified erosion of property value within communities.
It may be true that some people have legitimate non-investor reasons to sell their property like relocation for work, retirement, etc. and the amplified erosion of value was the proximate cause of their property being worth less than their mortgage amount.
It may be true that some of those people don't walk away from their loan agreement as a moral decision even though they have the mental skill to incorporate a legal strategy that is better financially.
It may be true that the government will inject funds into the finance system to cure problems for financial institutions hurt by the amplified erosion of value.