Using terms like 'ripping off' shows a lack of understanding as to how monopoly businesses are regulated. The regulations are highly formulaic and based on agreed allowances for operating costs and acceptable rates of return for investent in capital. These rules in turn enable the company to raise both equity and debt finance.
Increased capital spend leads to higher prices - otherwise the investment simply won't happen. Delaying necessary investment simply leads to a more significant price shock further down the track. Would you rather a 30% increase in three years time than 8% today (together with deteriorating services in the meantime)? That tends to be what happens when you delay investment in asset-intensive industries.
That's even before you get to the multiplier effect of the investments being made (especially important in times of recession when investment elsewhere is subdued) and the fact that anyone with a pension fund indirectly owns shares in a number of such utlities.
