As you undoubtedly know, there are both ethical and unethical ways to make a profit. While being profitable is no doubt anyone's goal, the assumption I would have when dealing with a recruiter is that he/she would try to find the best suited candidate for a company, for the salary that the company can afford.
Similarly, while a candidate may not technically be the "client" in that he or she might not be paying the recruiter directly, my expectation as a candidate, or an employer would be that the recruiter deal honestly with the candidate and work hard to see that there's a good fit between the needs of the organization and the needs of the individual.
No doubt these are idealized expectations and no recruiter ever does it perfectly. Something like no developer or team can consistently crank out error-free programs ahead of schedule and under budget in a manner that fully meet's the client's expectations. ... We are all human and produce less than perfect results, despite our best efforts.
If we're going to boil it down to a single ethic to follow, I'll stick with the Golden Rule:
http://en.wikipedia.org/wiki/Golden_RuleSo, they were being "un" professional, in that I felt that they were not living up to commonly held expectations that I would have for them, or that the individual who was emailing them held. In this case, it's a pretty low standard. They didn't provide simple follow-up with the candidate after he was informed that he wasn't selected for the positions.
