Quart

Oh, at my last job I used my Leatherman a ton. Wire cutters, screw driver, pliers, etc. I used the blade for opening boxes and stuff too. I don't know that I'd say everyone needs one, but they are pretty handy. I don't usually carry it anymore at my new job since it's pretty different, but I still occasionally find myself reaching for it.

To the OP question, I would say everyone should have a "go bag" with essential stuff you need in an emergency that's already packed and ready to go. A multitool is a great addition to a Go Bag since it can take the place of a lot of tools in a compact way.

Every time I go to buy a first aid kit I realize I don't really know how to use anything inside besides like the bandaids and simple stuff.

There are some Leatherman tools without blades: https://www.leatherman.com/knifeless

And lots more options if you look at multitools from other companies.