These collective nouns are mostly from an old book, and half of them in there weren't ever meant to be serious.

https://en.wikipedia.org/wiki/Book_of_Saint_Albans

I feed crows on my nightly bike ride. Sometimes there are multiple crows, the proverbial "murder". If there are just a few, as far as I'm concerned it's just a manslaughter...

Well they can't call the company Murder Inc, can they?