. . . They are simply "wearing" their signature in exchange for payment . . . This is also a very similar arrangement as to how newspapers and TV stations make their money....via advertisements, I would say that common sense would dictate that advertisements are not endorsed by these channels of information
EDIT: unless you personally endorse something you are not "signing" your messages with a specific advertiser
Would any of you have a problem with someone advertising a pedophile website in their signature space? Would you be willing to accept a payment from a pedophile website in exchange for advertising their website in
your signature space?
a
How about a "murder for hire" business? Would you be willing to accept a payment from a "murder for hire" business in exchange for advertising the business in
your signature?
Most moral and ethical people would refuse to use their own activity to assist businesses that they feel are immoral or unethical. Your decision to accept a payment in exchange for assisting a business says something about yourself and your opinion of the business.
You are essentially agreeing to become a paid employee of the business (you are getting paid, and you are doing work for them). As such, you are intertwining your reputation with that of the business. If you act in immoral and unethical ways, people will hold the business accountable for choosing to pay you and choosing to allow you to represent them. If the business acts in immoral and unethical ways, people will hold you accountable for choosing to provide services for the business and for accepting their "dirty money".
I think you should use some "editorial" discretion (to use a newspaper analogy) when deciding what paid signature to "wear". To answer your question, no I would not display either a pedophile website nor a "murder for hire" website in exchange for payment (or otherwise). Both of these examples are 100% clearly illegal in the US (where I reside).
To make the conclusion that either of these kinds of sites would be illegal, I could look at what services the website is offering, and look at the relevant laws and see that without question both of these examples would be 100% illegal.
Cryptominer on the other hand was not as clear cut. Yes, the chances of them being a ponzi were well above 99% (it turned out they were one), and yes the chances of them scamming eventually were well above 99% as well. However in the event that the less then 1% chance of them being honest and were going to actually pay investors what was promised then they would simply be making a very bad business decision, and it is not right to try to sensor that.
I also think that a reasonable person would be able to conclude that the returns being offered were that of a ponzi. I would consider investing in a ponzi to be similar to gambling. I would argue that the investors put their money into the ponzi with the hope of being able to make money off of the "interest" for some time and withdrawing prior to the operator running away with investor funds. I would consider this behavior to be similar to gambling at Prime Dice, however the "house edge" is likely much greater, but it is known that the house has an edge prior to people putting their money in.