Yuck,I have had bad experiences with attendants who are control freaks who cater only to families and old people. I have rights too.
Now Steve, perhaps they are control freaks. But it is done for a good reason. Perhaps you often travel alone, and would very much enjoy having your own seat. That is quite possible if the train does not fill up. But on a crowded run, the attendants are doing a good service in catering to families. I would not want to be separated from my child because there were not enough seats together. It helps knowing who is on the manifest, so they can block out some seats ahead of time.
Now all that said, I feel that there is a big problem with assigning seats to anybody. I have had MANY experiences in the past few years, where an attendant told me and my son what seats to take when we boarded, and when we got there, those seats were occupied. So now, we have to sit someplace else, and we take seats that were assigned to somebody else. You can see the mass confusion this creats. The crews are really not to blame, it's the people who did not remain in the seats to which they were assigned. The procedure needs some tweaking, and people have to be reminded to keep their butts in their own seats.
On the other hand, we had a very good experience a few years ago. We rode Train #80, the Carolinian, from Raleigh, NC back home to New Jersey. We had taken Carolina Business Class. When the train came into Raleigh, an attendant knew our names, and told us which seats to go to. When we got to the seats, there was a marker with our last name over the seat, in effect reserving it for us so nobody else would sit there. I felt this was a nice, personal touch, but unfortunately, it's never been duplicated anywhere else since.