It does seem odd, especially as Baham Mammas West was shown off in an obvious way in one of the screenshots with Franklin on a Bike. Seeing as LA has one of THE biggest clubbing scenes, yeah, it's kinda bloody stupid that not even ONE place is freely available to go into, Teqi-La-La looked great, but that was empty because it was pre-show, and we're never allowed back in after that!? Based on one of the biggest and well known Rock bars in America and we only see it briefly in one side mission many people would pass over.
Think of the brilliant side games each character could have, Franklin could be a smooth dancer like Luis, where as Trevor could have like a mosh pit mode, imagine going into Teqi-La-La as Trevor, heavy metal and punk playing, people jumping and fighting, and just throwing yourself into the crowed and using QTE's to knock people out whilst still dancing to the music.
Since GTA V is influenced heavily by Michael Mann's HEAT, they could have expanded it with a Collateral influence too, since it was another big Michael Mann hit. I wish, for the upcoming DLC, to have shootouts in nightclubs, perhaps a fully fledged storyline where Franklin takes over a taxi driver (since he probably owns Downtown Cabs by the end of the game) to do Lester hits, as a tribute to Collateral.