I like Trish, but I can see why she has annoyed Dylan.
It's all about the food.
Firstly, she ate lamb chops (chops - plural) for a night time snack. That would have formed the basis of main meals for at least two housemates, yet eaten as a snack. Lamb chops are expensive too, so definitely not something you would have as a snack where food is on a budget or rationed.
I don't think this was the only occasion she has done something like this either. It's greedy, and incredibly selfish. Dylan is trying to make sure the food lasts between shopping lists. Not his job, I know, but someone really needs to step up and do it in that type of environment.
Trish also knows all about running a house on a budget - unless her salary is higher than Kerry's !
There is absolutely no way (in my opinion) that she would do that at home, and I can well imagine her reaction if she walked into the kitchen to find her partner or child making a £5 snack from her weekly food shop