And yet again, you're making the downright false assumption that everyone sees it an unethical. Which they don't. In fact, most see it as a necessity.
No, I'm making the assumption/statement that, to some degree, it (or, at least, some of it)
is unethical. It's very easy to see something as either not unethical or necessary if you're ignoring or (spuriously) justifying unethical action. A lot of really nasty shit has been done over th'course of history while a majority of people thought said shit wasn't unethical, or was a necessity, or had some kind of excuse why it was acceptable even if it wasn't ethical.
Which brings it back around to 'will I be harming this organization more, or myself more?' With the answer quite obviously being "I am the only one who is hurt by doing this, as it in no way impedes their goals, and will only result in those with less concerns about privacy be those in charge."
Whether the organization is hurt by one's refusal or the one refusing is hurt by refusing, is
utterly irrelevant to whether
aiding the unethical actions of an organization is or is not ethical. There is literally no connection between those points. Being unable to influence the actions of the organization in question by your refusal or experiencing some degree of personal loss because of it does not magically make going on to commit unethical actions, ethical.
Yes, it's one of the great pains in the ass about attempting to put ethical concerns at the forefront of one's decision making. All too often it means losing out on very advantageous things, or accepting that you've traded an ethical foundation for said advantages.
There's something to be said for the last bit -- infiltration, so to speak, is a thing -- but in that case a person's basically saying, "By committing little evils, I can prevent larger ones." That doesn't change th'fact that they're committing unethical action. It just means they've got a goal they consider worth the immorality. That goal may be worth it -- sometimes it's even admirable, in a certain, that a person is willing to shoulder that burden in order to prevent a greater degree of immorality. That doesn't change the nature of the acts in question, nor does it entirely excuse the person in question for committing such acts.