The Butterfly Effect 2

@Theodore_Kritikos​ It's complicated. As explained at https://help.imdb.com/article/contribution/titles/title-formatting/G56U5ERK7YY47CQB# :

The way in which media content is released to the public is constantly evolving; some of our title types though relevant at the time are no longer applicable to some of the titles released today. This is an area we will look to address once we have completed the migration to move all areas on the site from our existing infrastructure. Until we can define these titles appropriately within our systems please use the existing title type that most applies to the title in question. Please note that IMDb reserves the right to amend any titles where we feel that another title type is more applicable to the title in question.

So, for example, movies released straight to subscription-based streaming services are now classified as theatrical films by IMDb:

If a standalone title is first released via a subscription-based streaming OTT service it should be submitted as a movie, for example, Roma (2018).

As those policies were not necessarily the same in 2006, I am guessing that as far as IMDb could determine, The Butterfly Effect 2 was first released theatrically somewhere (I don't know which country) before it had its first DVD release anywhere, thus making it eligible to be considered a theatrical film.