I guess it depends on what you believe stats are for. If you think that they are designed to "reward" players for doing what you think is good, then you should keep errors out. If you think stats should reflect what actually happens in reality (namely, a person's knack for, you know, actually getting on base), then you should include it. Because at the end of the day if you're standing on first it doesn't really matter how you got there as far as winning the actual game is concerned.