I imagine an aristocrat household maid would get a better pay (and other perks, such as free housing) than the serving staff at a random restaurant. Seeing how there are a number of maids, her current job ought to be easier as well, aside from needing to listen to a rude bocchan. However, nothing says the seniors/owners at the restaurant wouldn't also give her angry lectures. At the end of the day, the restaurant is lacking staff for some reason. What reason? Maybe it's not known as an attractive place among potential workers.