I run it on both. If you need to provide some UI context, being able to reach in to the state and query it is a life saver.

Imagine Advance Wars. Their unit movement is very subtle.

You can choose the path the units travel, which can turn in to a forced action if you stumble onto an ambush unit. When you reach the end it tells you the outcome of your battle before you confirm you want to engage in it.

Doing logic only on the server and sending down a list of possible moves is going to get pretty heavy. Querying for each square of movement is going to be a latency nightmare.

Edit: actually, I think the movement ambush is from a clone. Although the arrow movement from the original is still complicated. That doesn't weaken the argument: imagine getting half way in to dev and realizing you can't add that feature with your architecture.