To say that Scrooge is in anyway similar to Cratchit, would be the same as saying that evil is the same as good, or that hate is the same as love. But if one looks closely at the aforementioned opposites, one can ironically find similarities.
First, both Scrooge and Cratchit work at the same place, which is Scrooge's business of loans and real estate.
Second, they both are men who live in the Victorian era.
Third, they both have a love for Tiny Tim. And as the narrator tells us at the end of A Christmas Carol, Scrooge becomes a second father to Tiny Tim.
Lastly, Cratchit knows how to celebrate Christmas, which Scrooge once did in his younger days, but learns once again to celebrate Christmas by the end of the novella.