I believe some strata managers hold accounts in non-interest bearing accounts because in NSW at least the income form the interest is supposed to be added to the taxable income of the individual owners.
Apportioning the income so that it can be taxed correctly is often considered to be not worth the hassle either for the owners or for the Owners Corp. Unless the tax laws have changed recently, the same also applies to income from things like the sale or rent of common property.
I believe there is also a tax impost for unspent accumulated Sinking Funds – perhaps someone with a better tax brain than mine have could illuminate us.