Describe a person who intentionally uses a saying out of context for their own purpose

This manager worked in a grocery store. It is a hard job that requires him to arrive at the store at 5:00AM, do various tasks to make the store ready, handle deliveries, staff management and unexpected issues.

He had this habit of always sarcastically saying "Just another day in paradise" often saying it to others but most often muttering it to himself. He did this every day, multiple times a day.

One day while he opened the store in the morning he got shot dead by robbers.

With do you call it when he "butchers" the saying intentionally.

What do you describe someone who intentionally uses a saying out of context for their own purpose?

Not necessary only negative but rather describes the act of "butchering/abusing" the saying for your own purpose.

Another example for clarity:

Every time John drinks a glass of water he says "I just touched the hand of God"

I thought of hypocrite but that doesn't fit what I'm trying to say.

Solution 1:

The manager in question was probably being facetious as a means of venting his frustration through deliberate/forced humour.

ODO:

facetious ADJECTIVE

Treating serious issues with deliberately inappropriate humour; flippant.
‘a facetious remark’

‘Forgive me for being facetious in these desperately serious times, but sometimes ridicule is the only release from anger.’

‘I realize he was likely being facetious with discussing how he's perfect, but it still amazes me that he'd say it.’

Solution 2:

The people in your examples are using irony to express their sarcasm.

irony the expression of one's meaning by using language that normally signifies the opposite, typically for humorous or emphatic effect : “Don't go overboard with the gratitude,” he rejoined with heavy irony.

sarcasm
the use of irony to mock or convey contempt : his voice, hardened by sarcasm, could not hide his resentment.

Irony is the implicit humor in the contradiction between what is meant and what is expressed, or in the discrepancy between appearance and reality. An example would be to shout, in the midst of a hurricane, “What a perfect day for a wedding!”

Although sarcasm may take the form of irony, it is less subtle and is often used harshly or bitterly to wound or ridicule someone. Unlike irony, however, sarcasm depends on tone of voice for its effect (: “a fine friend you turned out to be!” he said, with obvious sarcasm).

New Oxford American Dictionary

Solution 3:

A cynic?

From Dictionary.com:

cynic: a person who shows or expresses a bitterly or sneeringly cynical attitude.

As per your question, a cynic would "intentionally use a saying out of context for their own purpose." For example, rather than saying, "Every cloud has a silver lining," a cynic would say, "Every silver lining has a cloud." Or rather than saying, "The glass is half full," the cynic would say, "The glass is 75% empty."