the salty-dog grunginess

[Coffee Break]

I encountered the expression "the salty-dog grunginess", but am struggling to understand it. Could you please let me know what it means? Here is the excerpt:

“So why do you come here?”
“I like the salty-dog grunginess.” She too could affect being intentionally flippant.
“Be serious. Do you miss him?” I proposed, as if to help her see the answer staring her in the face.

- André Aciman, Eight White Nights, Third Night

This is a novel published in the United States of America in 2010. This novel is narrated by the nameless male protagonist. The protagonist meets Clara at a Christmas party in Manhattan. Now, the protagonist is at a luncheonette where Clara and her ex-boyfriend used to come.

I googled "salty dog" and found that it is the name of a cocktail, but I am not sure whether that meaning can fit into this context. Would it perhaps mean "sailor"...?
I am wondering what that means, so I am asking for your help.

 

[Barque]

"A salty dog" can refer to a sailor. The "salty" comes from the fact that seawater's salty.

The reference to grunginess is because sailors are stereotypically not very refined.

Is the ex-boyfriend a sailor?

I encountered the expression

I came across the expression...

 

[Coffee Break]

@Barque,

Thank you very much for the explanation.
So "salty dog" here refers to the sailors rather than a type of cocktail!
She is saying that she likes the atmosphere of the luncheonette which is not refined and likely to have sailors as its patrons/customers.

Is the ex-boyfriend a sailor?

Actually, it is not clearly stated what this ex-boyfriend does for his profession, so I cannot be sure, but I guess he is not a sailor as far as I know.

I sincerely appreciate your help.