Hume's Guillotine, Final Form

Universal morality is a contradiction in terms. Good and evil are only approximately real.

If evil is unrewarding in the long term, you don't avoid it because of morality, you avoid it because it's imprudent. E.g. hard drugs. Costs are bad mmmkay.

If evil is rewarding in the long term, it's not evil. Even if it imposes costs on others, then you can pay off those affected out of the profits of evil. Everyone benefits. Nobody is harmed. Not evil. E.g. waste disposal.

Assuming evil exists, there is no such thing as evil. QED. 

There is no ought from is because there is no ought, period.

What exists is the tension between short and long term. Drugs: good high, long crash. Imprudent. But, worth talking about. The short term is easy to see and the long term more difficult; it's worth reminding yourself and others that the long term is bigger than the short term and thus worth more. 

In the case of short term costs and long term profits, but the costs are borne by others: they will fight back, making the costs higher and higher until you see no profit, and then you won't do it unless you're an idiot. There are in fact no long term profits. Indeed you will likely see this very obvious response and not even attempt it in the first place. Or you will pay them off to let you do it anyway, thus reviving the profits. Edge cases aside, they will charge you the market rate. 

Naturally some try to trick you into letting them impose costs on you, and this approximation of evil is a close approximation. 

It is important not to let them get away with it unless you want to die.

They will try to tell you costs are not costs. Remind them that costs are in fact costs, and any attempt to impose costs will be met with imposing costs right back. Violence, if you will. It is always the case that you can inflict enough damage on someone that their attempt to unilaterally extract value from you becomes unprofitable. The only real question is whether you're a coward or not. 

Even in the case they're too stupid to acknowledge deterrance, that means they are stupid and weak. As long as you're not totally pathetic you will be able to exploit their stupidity to get them killed or otherwise neutralized. 

In a sense there's a pseudo-ought. If you value a thing, there is some action that leads to you getting that thing, and some actions that don't. You ought to choose the actions that work, not the actions that don't. A rather degenerate [ought]. Again, merely a subset of prudence. Be wise, not foolish. If you were foolish and it worked out for you, it wasn't foolish; if you were wise and it didn't, it wasn't wise. Trying to be "moral" per se isn't wise.