We have encountered he Tiny Timmy Dolls before - Timmy III used the Mark Ones for rather nefarious purposes, though. (They could not talk, but they could see...)
I just thought that it would evoke a more obsessive impressive image if Detective Logan's file regarding Bettina Timmy's exploits is a huge stack of paper rather than a computer file of such-and-such MB.
And speaking of Timmy III - upon his assassination, it was Detective Paige Logan who let the investigation, with Tiny being her primary suspect.
And even though Tiny officially is off the hook by now, in Paige's mind, she is... not.