Hi. I saw the examples how to use nHibernate 5 async features, something like this.

async Task<Item> GetItems(){
 return await _session.ListAsync();
}

Why should to use async/await instead of just?

Task<Item> GetItems(){
 return _session.ListAsync();
}

It lets us avoid the async/await overhead. Or maybe are any other reasons to do like in the first example.
I have read the documentation but didn't find an answer. Maybe are any limitations and the second example will not work?