So what's a human supposed to do on Europa? Operate a hammer and icepick? That doesn't sound very productive. That 45-second figure on Mars sounds hyperbolic, since on good days, the rovers can actually go pretty far and take lots of pictures.
But here's what I don't get about people who make comments like yours: Instead of looking at current missions and wishing that humans were there to do it better, why not instead ask what humans would do in space, and wish for (and design) machines that could do it as well. I mean, be concrete. For all the mission specific objectives (beyond: what happens to a person there?) that manned missions have - whether it's reconnaissance, construction, experimentation, etc. - I am pretty sure that it would be less expensive and less risky to make robots that could preform them equally well, less expensively and more safely. I think that's been the case since basically the Apollo era, when human lives were cheap and autonomous systems were miserable. That's the good reason why the Apollo era ended in 1972. The NASA home run of the 70's was the Voyager program. Then we pissed away the 80's shuttling people to LEO for no very good reason.
And if you compare the primitive rovers of today to manned missions, keep in mind also that the latter would be several orders of magnitude more expensive, and what amazing advances we could make if those budgets were going to robotics and autonomous systems. Maybe those robots really could do in 45 seconds what yesterday's rovers take a day to do. I mean, for fuck's sake. We have cars that can drive better than my mom.