I was discussing this elsewhere and decided to make a post. Genteel poverty, which is being experienced by the Bates, the Dashwoods to an extent, and possibly the Prices (though I don't know if they qualify as gentry), is different than actual poverty. The reason they struggle is because they have to keep buying things that keep them in their class, such as proper clothing and food to feed visitors. For example, the Dashwoods host the Middletons for dinner every time they dine at the park. That makes them participating members of the gentry, but it's probably eating up a lot of their budget. It's probably also why Mrs. Dashwood refuses to visit anyone else, they can't afford to host anyone else! Mrs. Grant also does this by the way (in Mansfield Park), she hasn't chosen to visit with the Rushworths and start this endless back and forth, so she doesn't accompany the others to Sotherton.

The Bates would have to do this too. They don't ever host Mr. Woodhouse because of his eccentricities, but if they are invited to dinner they would be expected to host back. That pork that Emma sent them likely was shared with Mrs. Elton or Mrs. Cole or whomever they needed to invite back to dinner.

There is a novel called Cranford by Elizabeth Gaskell that is all about this. It's about a small town mostly inhabited by spinsters and widows who mostly have incomes similar to the Bates's, and how they all collectively pretend that they can afford to be gentry. Like baking the treats for your friends yourself but pretending that your maid did it. Or pretending you have candles burning at night but actually rushing to light them when someone knocks on the door. They all find ways to save in other areas of their lives so they can maintain the trappings of gentry.

But the point is: they can afford to eat and clothe themselves and have a maid of all work, an income of 100ish pounds a year is something you can live on and they don't have to work. They are poor in comparison, not actually poor.