The original KB's was a well designed club that was run right for a long time. I am aware that some people would spend time there sipping on a glass of water and literally buying nothing. If folks don't spend at a club it folds.
KB's reminded me of a club in my old home town where I spent a lot of time (and money). They had good house bands, ladies night a couple days a week and brought in some top bands. Men always paid a cover charge. The place opened at 5:00 p.m., ran a two for one happy hour until 7:00 p.m., and was always filled and so popular the owners eventually bought the land next door and built a new much larger club using the same floor plan but greatly expanded. They tore down the old building and used that land for parking. They maybe had two acres of parking at this point. This club was a success for fifty years.
This video shows the layout. While a latin band is playing in the video the Caravan East was primarily a country-western venue.
Caravan East Night Club in Albuquerque, Features Live Music by Severoy Grupo Fuego on Vimeo
The neighborhood changed over the years and became so rough the locals started calling it the "war zone". That is likely why they closed. It became unsafe to even drive in the neighborhood, especially at night.