We use signalling to give people the impression of who we are. Think of the peacock growing the massive tail to signal to the peahen that he is not only healthy but has access to the best food and free of predators to grow it.
To clarify, only individuals who are elevated in status have usually acquired the capacity, resources, money, time, and influence to behave altruistically. Only wealthy people, for example, can afford to donate large sums of money. Thus, if someone behaves altruistically, this person is perceived as elevated in status. This person is more likely to be respected and even trusted.
That expensive car and house putting someone in debt up to their ears? It is signalling that he made a bunch of money. Potential investors are looking for whether or the people involved are successful. These outward signs can only help.
The same signalling with altruism struck me as interesting. Naturally it fits the idea. By throwing money at a cause, one signals that would has lots of money to give away on stuff like that. It strikes me as funny because the Trump Foundation gave to causes with other people’s money. It signalled Donald Trump’s ability to give away money only it was money from other people. Knowing the truth about the source suggests maybe his money was so tied up in real estate he could not do it on his own. And suggests perhaps he does not have the vast wealth he portrays.