SueEllen's is effectively the women's bar, and has a recital hall on the second floor (you could do a piano concert there). A "Lite Band" was there playing, with one of the musicians saying he wanted to play in G Minor.
Why do are gay businesses in conservative Dallas (eg. Lawrence v. Texas and 21.06 repeal)? One big reason, besides the large young professional and collegiate population of a major city, is that real estate prices are lower than in many other places. There is more room, more land, more physical space. It costs less to build these spaces in cities like Dallas and Houston than in many other places, especially in Washington and New York. Lower real estate prices in an area obviously benefit some businesses and some people, and the gay bar business is doing better probably because of the mortgage crisis and fall in real estate prices almost everywhere. The neighborhood between Oak Lawn and downtown has a lot of new condos (and streetcars) and looks to be in great shape.
By comparison, it costs $10-12 to park in a supervised lot in Dallas near the bars; in Washington DC it's $15-20.
(note: url title of post has "book" instead of "boom" because of an initial typo.)