I reckon, the fact that these people seem to have a lot of money, has summat to do with being "tigt" and a healthy respect for money too. What's the point in having a wad of cash, if you're going to throw it out the window?
I find they're the most likely to argue about what they owe too.
Even when confronted with the facts, they still grudgingly pay up. The big car on the drive and expensive house etc. Usually means they're like swans, all serene on the surface, but legs paddling like hell underneath
Their lowly window cleaner has no mortgage, and no debts.