Wealth is created and destroyed all the time without transactions or exchanges occurring to mark the value of every asset. The value in a market is set by its most recent transactions, and it is usually a small percentage of an asset or commodity class that trades hands that marks the changes in price.
Consider the home-equity refinance picture these past few years. A long-time homeowner, for example, might find they have additional equity in their home to borrow against. They have not bought or sold. There was no exchange between buyer and seller marking the appreciation. Their asset ownership occurs against a backdrop of appreciating housing prices. Voila, wealth creation. If prices decline, wealth is destroyed.
Again, if a large percentage of an available commodity in a given market exchanges hands on a given day, then pricing might approach perfect efficiency and wealth would generally be transferred not lost. Yet that is not what occurs, even in relatively liquid markets such as stock. The effects are amplified in markets such as housing.
Some additional aspects to consider are (a) on the finance side, the impact of leverage on asset values, revenue streams and nominal wealth creation, and (b) the impact of the cost of borrowing and monetary policy these past few years, the net effect of which has been to increase nominal wealth at the expense of the currency itself.
