My gma used to check these each year for every family member. It would take hours as she had a bunch of sibs and so did my Gpa and each of those sibs had a ton of kids, etc.... Boy if she found you had unclaimed $ you got a lecture on responsibility - cause it is not responsible to not know where your $$ is.
Now my dad checks for each of us every year. His lectures are apparently worse than Gma's were, at least according to my cousin and brother. I have yet to have unclaimed money. Never had enough to not miss, I guess.