A lot of it is down to lack of transparency. I don't necessarily mean highly paid staff but cases of money being spent on cars and holidays. Or services like Pieta and Jigsaw who it seems just...don't provide the service they claim to provide. And huge duplication of services. A lot of charities are providing things which would be far better dealt with by the state, and charities are kind of permitting the state to not do it.
Also I think some of it might be down to a general lack of standard of living. I live with my parents, can't afford to rent even though I've a good job (yes I know it's great I can live with my parents many people don't have that etc etc). I used to work temporarily helping people with social welfare stuff and it honestly just made me angry that they were able to get houses on their own, not sharing with flatmates, were able to be pretty picky with areas, all while having basically never worked. And like I don't have any of those choices? I feel like there's a lot of "middle class" people stuck in actually pretty shitty living conditions, having spent years studying and working, if just makes you less inclined to help people less fortunate than you who often seem to be more fortunate than I am.