Altrusim is Not Cooperation

The fundamental theorem of sociology is the prisoner's dilemma. 

Though the classic version is missing the [no interaction] column. Showing the originators face by returning explicitly to the perps caught by the cops...what if they decided not to perpetrate in the first place? Left each other alone? You can't be tempted to betray your fellow if they are not your fellow at all. Also they wouldn't be caught by the cops in the first place.

Altruism is not cooperation. Altruism is not minding your own business. The only reason I don't say altruism is inherently defective is that sometimes it mimics a cooperative trade.

Altruism doesn't ask if you want the gift. Nobody asked the slaves if they wanted to be freed, they were just punted off the plantations. This worked so well they immediately had to come back as sharecroppers. 

All altruism is callous altruism.
If it is not callous, then you ask first. "Hey man, do you want some X? Maybe some Y?"
Zeroth problem: this gives them a chance to refuse. What is the altruist supposed to do if they say no?
First problem: now it isn't altruism, it's negotiation. Any single X or Y is negligible. What they want is an ongoing supply of X or Y, and look, let's be real here, you're not doing that for free. Even in the extraordinarily unlikely case that the altruist will freely support another person unconditionally, the constant contact will form a relationship. It's now a social thing, not an altruism thing. Can't be stranger altruism if they're not a stranger. 

If it's negotiation, it's a trade. If it's a trade, you're not doing it for free. If it's not for free, it's not altruistic. 

It's just that, occasionally, had you asked, they would have said yes, so it mimics a cooperative trade. However, the fact you didn't ask displays the callous solipsism this "altruism" in fact comes from.
As per Last Psych, in theory the narcissist could pretend not to be a narcissist, and from the point of view of everyone else, they would be cured. Problem: solved. Great. However, the issue with lies is that, when push comes to shove, the truth comes out. Lies are unreliable. Untrustworthy, even. How counter-intuitive. Under stress, the exact time it's actually important, the narcissist - whether a standard narcissist or a treated narcissist - reverts to their true personality. The personality they hate so much they have to pretend it doesn't exist. Don't worry, you'll hate it just as much. Conquest #1: nobody knows a person like they themselves do. They spend exactly 100% of their time in the company of said person, after all.
If an altruist is doing you a favour, first, grab your wallet before they get their fingers into it. Second, come up with an exit plan. They do not have your best interests at heart, and this will reveal itself the instant the altruism is infinitesimally inconvenient to the altruist.

Of course if you've glanced briefly at psychological egoism you already knew. The altruist may not get classic materialist rewards like money or other goods, but they would only engage in altruism if they found it rewarding in one way or another. The begging-enabler gives money to the alcoholic head-case because they either value warm fuzzies more than a couple bucks, or because their guilt is holding them hostage. Pretty lame hostage situation that can be bought off for the price of a coffee, though. Guilt, that was cringe.

The altruist is getting paid. If they weren't, they would quit. That's simply how decision-making works. The mind chooses the most valuable of the available options. Basically by definition; what it chooses reveals what it finds most valuable, modulo some ignorance or oversights. 

When the altruist claims to be altruistic, they are lying. Lies, as I've covered, are unreliable. The altruist says they're in it for you, and they are not. Plan accordingly. 

When you genuinely want to help someone, get paid. Offer them something they want. Confirm they want it when they demonstrate they're willing to give up something to receive it; avoid wasteful offerings. Get paid explicitly, forthrightly, and honourably, instead of lying about your wages. Fund further offerings of value using the price you charge, so the person you want to help doesn't run out of the thing they need help with. 

Sustainability isn't enviro-Nazis. Sustainability is getting paid market value for the providence of value. Charity actively weakens the victim, and is usually intended to. Trade is antifragile. Trade, as per the prisoner's dilemma payoff matrix, makes you both wealthier than you would be had you minded your own business, which it does by making the relationship into your business, which you can then mind anyway. Indeed literally a business. 

Greed is not a sin. Altruism is a sin.