One of Dicken's motifs in Great Expecations is the great folly of the burgeoning middle class of his era that wishes to rise to what he considers a frivolous aristocracy. The character of Pumblechook represents these ridiculous members of London's middle class, and provides comic relief in the novel as Dickens satirizes him.
When Pip arrives at his shop, for instance, he notices that Pumblechook "appears to conduct his business" by watching the other shopkeepers who, in turn, watch each other except, ironically, for the watch maker, who keeps his eyes on his work. Again, as the most ungentlemanly Pumblechook stingily doles out little for Pip to eat, the pompous man tries to impress Pip by asking questions about arithmetic. This is done in his hopes that Miss Havisham ask Pip to do a problem, and Pip will know the response and reply that Mr. Pumblechook has taught him.
As Pip eats his meager meal of bread and watery milk, Pumblechook eats in a "gorging and gormandising manner"--anything but gentlemanly or hospitable, as well. This action also serves to underline the hypocrisy of the man to whom Pip refers in another chapter as "the greatest of swindlers."
In further satire, Pumblechook is extended no hospitality himself when he arrives with Pip at Satis House when he attempts to go through the gate that Estella has opened for Pip:
"Oh!" she said. "Did you wish to see Miss Havisham?"
"If Miss Havisham wished to see me," returned Mr. Pumblechook, discomfited.
"Ah!" said the girl. "But you see she don't [sic]."
She said it so finally, that Mr. Pumblechook could not protest. But he eyed me severely--as if I had done anthing to him!--and departed with the words reproachfully delivered. "Boy! Let your behavior here be a credit unto them which brought you up by hand!"
This chastisement of Pip, of course, is another extension of Pumblechook's "hospitality." While he is servile towards Miss Havisham in his aspirations of rising above his class, he is cold and cruel to Pip and others beneath him.
If we are just talking about Chapter 8, I guess my answer would be "not much." Uncle Pumblechook does not really give Pip all that much in the way of hospitality before he takes Pip up to see Miss Havisham at Satis House.
He does feed Pip, but that is all and he does not exactly give him a lot to eat. Instead, he gives Pip some bread and butter (Pip said that there was as much bread as possible to as little butter as possible). He also gives Pip milk (but Pip says that there is so much water in the milk that you can barely tell it's milk.
besides giving me as much crumb as possible in combination with as little butter, and putting such a quantity of warm water into my milk that it would have been more candid to have left the milk out altogether,—his conversation consisted of nothing but arithmetic.
Meanwhile, Pumblechook himself eats bacon and hot rolls.