Okay, as I understand it (this is mostly assuming it's similar to the TX legislature during the redistricting kerfuffle), the majority has enough votes to pass a law that the opposition feels is unfair. So the opposition lawmakers leave the state in order to deny a quorum, making a vote impossible until they return.
Leaving the state is a stalling tactic, which reliably focuses media attention on the issue but probably won't change the outcome. However holding a vote is, for all intents and purposes, capitulating. In what way is a strategy that requires more co-ordination, brings more publicity, and increases the chances (however slight) of success not "trying"?
edit: I think I get the impulse here, to see physical presence + official opposition as being more authentic resistance than physically running away, but that's taking the battle metaphor too literally. Fighting for something in politics means doing whatever gives you better odds of a better result, and sometimes that means obstructionism and baldfaced publicity stunts. Hell, that's all the GOP's done the last two years and no liberal I know would say they haven't been fighting.