I think your completely right. I was once talking with an angel about one of the companies they had invested in and got the reply "I don't know what their doing I'm just an investor." Whether this is a good thing or not is up to discussion.
I don't see that as much of an excuse. Investing in a company isn't like paying taxes; you voluntarily decide who to invest in, and ethically (if not legally) you have some responsibility for their actions.
