the season is over", the statement is funny because the seriousness and precision of the language seems comically out-of-keeping with the informal situation.
The following quotations speak for themselves. (The "learned" elements are italicized.)
Gwendolen in the same play declaring her love for Jack says:
"The story of your romantic origin as related to me by mamma, with unpleasing comments, has naturally stirred the deepest fibres of my nature. Your Christian name has an irresistible fascination. The simplicity of your nature makes you exquisitely incomprehensible to me..."
Eliza Doolittle in Pygmalion by B. Shaw engaging in traditional English small talk answers the question "Will it rain, do you think?" in the following way:
"The shallow depression in the west of these islands is likely to move slowly in an easterly direction. There are no indications of any great change in the barometrical situation."
Freddie Widgeon, a silly young man in Fate by Wodehouse, trying to defend a woman whom he thinks unduly insulted, says:
"You are aspersing a woman's name," he said.
"Don't attempt to evade the issue," said Freddie...
"You are aspersing a woman's name, and — what
makes it worse — you are doing it in a bowler-hat.
Take off that hat," said Freddie.
However any suggestion that learned words are suitable only for comic purposes, would be quite wrong. It is in this vocabulary stratum that writers and poets find their most vivid paints and colours, and not only their humorous effects.