One potential use of a trust is to dictate how the funds can be used from beyond the grave. I know of a woman who left her assets in a trust for her 4 kids, with all kinds of restrictions on how the money could be spent (ie. need a new roof for your house? ok. want to buy a Maserati? nope).
Eventually the kids got the courts to grant access to all of the money without the restrictions. I don't know what the process was, but it wasn't quick or easy.
At this point, I don't have much desire to control our money beyond the grave. Our kids are probably going to be in their 40's or 50's by the time the second of us dies. Hopefully the amount they will receive won't be a life changing amount of money at those ages. I'm sure it will help, but we're not talking millions for each kid. I'm sure we'll continue giving much smaller amounts while we're alive. There may not be much left over.