Many long-time smokers don't leave it at one bowl, now or in the past, unless there's a good reason to. And no, people don't smoke "more" now, nonetheless; weed is MUCH stronger now, than it was in the past decades (5-10x or more). I'd say many people smoke more openly, however, if that makes sense.
These things allow you to carry your traveling stash and smoking device as one, compact item, that happens to be smokable while on the move; there's lots of other variations on this idea (Proto Pipes, for example). You could easily cram enough high-octane smoke in there to last all day, even when sharing widely, unless your tolerance is truly epic >.> .