Meh. I don't think there's anything ambiguous about the fact that they consciously sent unsolicited emails for what they've admitted are essentially marketing purposes. That they didn't think there was anything wrong with this, and didn't consider that this would be viewed as spam, I'll concede. But that just makes them ignorant / naive / unethical (take your pick). I don't think this is a hanging offence, but I do think that their "apology" is at best an exercise in self-justification.