re: Yes, battery acid is "wet"...snottites.
Agreed you wouldn’t want to put your hand in battery acid, but there are bacteria that would, e.g. snottites, or slime bacteria that live at pH 0.3 in sulfur-rich cave systems such as Cueva de Villa Luz in Mexico( http://www.i-pi.com/~diana/slime/villaluz/) . There are plenty of odd organisms to inhabit almost any environmental niche you can think of, at least here on earth. If life originated in the initial wet period on Mars ( a big if) it is possible that it survived into the second sulfurous stage, at least while there was water.
Andrew