We don't see what goes on all the time though, do we? It seemed like a lot of people agreed that Sam just takes the food, eats it and then leaves her plates for someone else to wash up. That would be piss me right off. Kind of surprised she would do that - she seemed a bit savvier than that but hey.... not the first time that initial impressions have been very wrong. She's an empty vessel basically.
As for Jack, it's all getting a bit mean on here about him. Yeah he's fat and unattractive. But he's not evil. I'm even warming to him a bit. Mainly because he hates Simon and therefore it is clear that he has sound judgement.