Not enough people have millions in the bank to make a difference if they get child benefit. That would mean 'unnecessary' payments of a tiny amount in comparison with the better living standards it would mean for lower earners. High earners would still be better off (than lower earners) and with less to spend their money on they would still have a lot of disposable income for non-essentials.
I didn't mention squeaking pips. I also think that the motivation for getting 'better' jobs is not all about pay, and what keeps people in the UK is about more than pay too. Some people would emigrate, but they always do, and we would quickly get immigrants to do the things they did, particularly if we offered a good standard of living and a happier population.
I dislike means testing for numerous (well-documented) reasons, but I pay tax, as does my husband, which is fair, as we both use the services it pays for. As you say, grannysyb, the rise in the state pension (Mr Dog gets it, but I am not yet eligible) will be swallowed up in council tax, fiscal drag and income tax before we start on the cost of living increases. It's annoying, but it's fair.