You can do em if you want. When you do deadlifts, you should sort of be shrugging, but not exactly. Just kind of putting the shoulders in proper alignment i guess you'd say, keeping them straightened.
You don't have to shrug if you dont want, but i mean, i've seen guys doing arm curls, then while their resting with the weights in their hands the do a few shrugs. It's sort of a do it if you wanna do it thing. But if you want big traps, DO IT!!!
Keep in mind i JUST woke up and am still half asleep, i hope this made sense.