and our daughter has orthodontic treatment without charge
I have to be "that guy". You were charged - and quite a bit for it, they just didn't hand you a bill after you received the service. When you factor in all taxes (VAT, fuel tax, TV tax, income tax, NHS tax, etc) even the lowest tax bracket in the UK is paying roughly 50% of their income in taxes.
Rubbish The lowest tax bracket is zero and accounts for income up to £10,600 in 2015/16, from £10,000 in 2014/15. In terms of indirect tax, VAT is not charged on children's clothes or "non luxuary" food, and is 5% for domestic heating and electicity. There are a number of other exemptions and it is on 20% for the rest.