Why is this profitable?
If the land is worth $1.5 billion, it should have cost PE more than $1.5 billion to buy the company. Then there would be no way to make a profit by selling the land, paying yourself, and letting the company go belly-up.
Why does PE keep doing this? Presumably because it works? But why does it work? Are the sellers less sophisticated at asset valuation than the buyers, and frequently lowball themselves? Or maybe owners/stockholders are sometimes just tired of holding this asset, want cash to reinvest somewhere else, and are willing to cash out at a discount?