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Nodes yield no personal economic benefit but are vital to the community as a whole, hence more altruistic.
No, you run node to not trust but verify about transactions (mainly incoming) of your own wallet. Also, privacy, as it's very hard to not leak data about different addresses in your wallet to a third parties with light client (except if using client side block filtering in a way Wasabi Wallet does it). It should not be altruistic. If you just run node but does not use it for anything yourself, it doesn't help Bitcoin network much.