That is true, but we have to remember that we are in another era of the CGI animation movies. Before 2006, these kind of flicks were truly movie events, as proven with the fantastic admission numbers films like TS & TS2, Shk1 & Shk2, FN, MI, TI, etc... (it's beyond me Ice Age 1 did not cross the $200m mark, but that's another story...).
But in that year the animation parade came and it made these movies less eventful and that led to lower grosses, lower openings, even for movies released too wide.
While I don't like Frozen, I have to admit it is the most memorable run since Shrek 2. Doesn't need to come close to that movie's admissions, but it came awfully close to Shrek 1, Monsters Inc, TS2 and is bigger than The Incredibles and practically every animated movie since then.