I think Victoria's family were quite well off. She talks about it in her autobiography. She was teased in school because her dad owned a Limo service I think, and used to drive her to school in one. Not sure what her mother did, but she's always been well off. Her financial state was improved even further with the Spice Girls, and before until well after her and David marrie, she was always the ones that was worth more, so she didn't marry him for his money - maybe it was the other way round!
Anyway, yeah £60,000 is a hell of a lot to spend on jewellery, but they don't need to save. I think the beckhams do do a fair bit of charity work but aren't creditted for it. About 6 months ago, they did lengthy hospital visits (and word is they also made a fairly substancial donation - far exceding £500,000) to the Special Care Baby Unit in Leeds Hospital in England. That was *not* for publicity, because they never got any. In fact barely anyone knows about that.
Anyway I'm going off the point. Yeah its a lot to spend, but they do good stuff too