No, it isn't. CPAC is always crawling with College Republicans and other student groups from all over the country. The sponsors and a lot of the exhibitors pay "scholarships" (entrance fee and hotel lodging) for them to attend in exchange for a little volunteer work. And the list of exhibitors subsidizing students is public.
Bottom line, Mitt might have paid for them to come, and they may have to work the Romney for President booth for a few hours, but otherwise the weekend and the straw poll are the kids' to do with as they like.