I think you misunderstood his point Karl, he is saying his BUSINESS has to pay a rediculous amount of taxes, not his personal income. He is annoyed with this, not (entirely) because it takes away from his income, but because it makes it hard for his business as a whole to stay afloat. This affects his employees, who in turn watch their money because of job insecurity, which affects other businesses who are now losing some of their income from those who would normally spend freely.
The trickle down effect of this is much greater than a few mothers struggling.
Put it this way, a lot of those mothers would have been employed before they fell pregnant yes? The reason they may be struggling is because they were laid off/had to take unpaid leave because their employer wasn't in a position to pay them maternity leave (due to having to pay so many taxes). If the businesses were looked after, they would be in a better position to offer maternity leave and a lot of those sturggling mothers wouldn't be in the position they are now.
Please note, this is a simpleton's thought process and is no way meant to imply extended knowledge of the economic climate in Australia