Totally normal, parents tell us this all the time. From completely different behaviour to the point where we just can't imagine the child ever doing those things, to sleeping when they never do at home, and other things. It's a variety of things, the 'everyone's doing it' is definitely a big one, different people, different perceived expectations, etc.
I have told parents (when discussing tantrums and tears over nothing in older children) that it is definitely easier for us as the tears do not effect us as much as when they are your own.

We also have children who sleep less than at home and things too. A big difference is often how many bottles a child will drink - especially a younger toddler, who can be a bit finicky with drinking bottles given by others. Most of the time they are just fine though.