With groups you can still invite your colleagues and you can share maps you made. With this you can quickly find maps of each other, with the caveat, everyone can see your maps.
If they would have gotten rid of groups, you wouldn't see if one of your colleagues has a new map available, or you would have to look for links of older maps that one of your colleagues shared.
So groups still serve a function, but if you want privacy, you need to pay.