That's a good point. The increase in asset valuations will later filter down to other goods and services eventually.
I also agree that deflation can also be a good thing for the less fortunate in giving them access to more buying power. The fear with deflation is that it commonly can lead to lower consumer spending on average thus leading to lower levels of production and layoffs/salary reductions. Why buy something now if you know it will cost less in the future? There have been some examples such as Switzerland which have experienced a period of 5 years of deflation without any widespread negative impact on the country's economy. Despite this, I personally agree with most economists that a healthy level of inflation is better for the economy.
Inflation is not always costing us more. Think about this nation's debt. Inflation will only help us pay off that debt in time and can definitely help all people, even the less fortunate can pay off their debt more easily.