Green’s Dictionary of Slang

(US) a very sordid bar or saloon.

1891		J.A. Riis How the Other Half Lives 213: The down-town ‘morgues’ that make the lowest degradation of tramp-humanity pan out a paying interest.
1903		H. Hapgood Autobiog. of a Thief 216: If one of them had five cents, he would go into a morgue (gin-mill where rot-gut whiskey could be obtained for that sum) and pour out almost a full tumbler of booze.
1909		I.L. Nascher Wretches of Povertyville 21: Adjoining it is a ‘Morgue,’ so called in the parlance of the street because the stuff dispensed there brings the consumer in time to its more gruesome namesake. [Ibid.] 48: The saloon [...] is like the ordinary Bowery morgue, the back room is generally filthy, poorly lighted, and altogether repulsive.