I'll chime in here as a "typical Utah Mormon...." blah blah blah
I know Seth from my time at BYU but don't have any ties to him other than that and we aren't "facebook friends."
That being said, I think he is a decent guy that made a poor error in judgement here. We've all done it from time to time, I know I have.
Everyone will have their own take on this, but Boston this year to me was about the city, paying respect to those that were injured and killed in last years bombs, and running brave and as one with everyone in the city. It appears Seth did this for personal attention and gain. This is unfortunate considering the timing and circumstances surrounding this years race.
Bottom line- Taking a step back and considering the gravity of this year's race, Seth would probably agree that he made a mistake and used poor judgement in his acts, however there are certainly worse mistakes one can make in judgment and we are all human so lets not kill the guy for it.