Carpe Omnious?
 

Saw the film Hard Candy. The girl use a the phrase "Carpe Omnious" or "Carpe Ominous"

Supposed to mean: seize it all or take it all. Can anyone confirm this translation?

Maybe it was "Carpe Omnibus"? "Omnibus" is Latin for "for all". It implies "for all people" or "for everyone", but... hell, Latin's a dead language.

Cape minibus is a vehicle of hippie carp

The correct latin for "seize everything" would be "carpe omnes." So that's probably what she was saying.

Omnibus is the wrong case. It's either dative or ablative, and commonly used with prepositions like "for", as in your examples ratbastid. Omnes is in the accusative, or direct object, case, which would be correct in this sentence.