Just because you're a mercenary doesn't make you dishonorable. A mercenary is nothing more than someone who provides a service. That service being their ability to fight. There's nothing inherently dishonorable about that.
This is true. Although, in my view, it can become more complicated than that as you may be asked to do things for your service that go against your personal view. In fact mercenaries do tend to pick and choose jobs, not just for the coin or danger facter, but also if they are happy to actually do it. Of course, a totally ruthless mercenary will do anything as long as the coin is right and that means ANYTHING.
I`ve been running a new game and avoiding the MQ (where the Dragons attack) for quite a while and it dawned on me from all the jobs I was doing that I was actually being a mercenary, even though that was not my original intention. I noticed I was also cherry picking my jobs, going from town to town,asking Taverners what was going or checking out incidents. There were some jobs where I felt I was being taken advanatge of so just said `No` or avoided and moved on.
That`s how I play the merc.