[Crazy Jetty]

Yeah, the lack of currency is a bother, and a headscratcher when they explain "People work jobs for their own betterment," when pressed about it. I sure never would have worked at walmart had I any real options.
Though... I don't know if they tried to present this in the show, if this is backstage infor, something my mind concocted when I was a child, or what... but somehow I got it in my head that they are given "Replicator rations" (I know for a fact Voyager did, but they were in an extreme situation. I'm somehow associating this with TNG, though).
Which makes a certain amount of sense. It isn't exactly currency, manages ship resources, and it also keeps people (Especially kids) from just making up absolutely everything they ever could want (You know... like what any Arker would do if given access to a replicator, lol).

As for travel time... I've always just turned a blind eye to that. Kinda have to. Especially with the Abrahms movie (Earth to Vulcan in a few minutes? I can accept it because they really had no time to deal with it in a movie, but yeesh.)