Bob Cratchit is not the Dickensian avatar of penury. He's working a job which would be middle class if Scrooge weren't such a miser. He's also likely doing the work of three or four clerks. But he's not impoverished. He's eking out a living which should be more comfortable, but he's still making do. He can't afford to take proper care of his sick child, but let's be real here: lots of people in Victorian England could have said the same, and did. It's why a shit ton of children died.
In fact, that could be a criticism of A Christmas Carol: it concerns itself with people who aren't destitute. If you've read my other toot about the book, you'll know I don't hold to the view that it's concerned with the salvation of the rich primarily, but by concerning itself with the well-being of a family like the Cratchits, who are a struggling white collar family rather than an impoverished one, Dickens could perhaps be said to worry about the wrong sorts of people.
But let's face it: the poor don't need to be told that rich people suck. No, Dickens' audience is the Bob Cratchits of the world, but the clerks and bookkeepers who make a decent wage, who might, at some point, find themselves in Scrooge's shoes. Scrooge, after all, started as Bob Cratchit.
This is one of those things which the audience of the time would have understood as context whereas the modern reader doesn't. Bob Cratchit is going to inherit Scrooge's firm in the end. He wouldn't have had Scrooge not changed, but Scrooge has gone from being Bob Cratchit to Scrooge and then, through his transfiguration by ghosts, to Fezziwig. Seriously, this is all in the text.
Which, it pains me to say, is a repudiation of everyone who sees A Christmas Carol as a socialist encomium. Dickens wasn't a socialist, or at least he wasn't displaying this in A Christmas Carol. The lesson of the book is much more Confucian: Be a good servant, then when you rise, remember being a servant and be a good master to those who follow in your footsteps. The proper progression of a good man, in the world of A Christmas Carol, is from Bob Cratchit to Fezziwig.
Yes, the book has excellent points to make about being consumed with greed, but the opposite of greed isn't Scrooge giving away all his money. He becomes, in the words of the text, "as good a friend, as good a master, and as good a man, as the good old city knew, or any other good old city, town, or borough, in the good old world." Notice that, "as good a master." Scrooge doesn't even stop being a money-lender, for fuck's sake. He probably continues to charge interest on loans, just on fairer terms. He doesn't give Bob Cratchit more than is due to a friend and servant.
This is all an extended subtoot about the meme saying that Bob Cratchit is a Dickensian allegory for penury who makes more an hour than most Americans do. Because it's not true. Honestly, think about it. Bob feels he's lucky to have the job, but he's not working for free. He may be the lowest-paid clerk in London or whatever, but he's still a clerk, not a mudlark or dung collector. He has enough to celebrate Christmas, albeit poorly. He's not wealthy but he's not begging. If that weren't true, why would he keep working for Scrooge? He's not indentured. It's a lousy job, but it's not slavery.
Anyway, people really ought to read the book rather than vaguely remembering a movie adaptation or whatever. Scrooge isn't even supposed to be that old. He's Marley's junior partner. People died younger in Victorian England. Etc.