Kind of a turducken thing?
Interesting. I like jerky and cheese as much as anyone but I prefer just sugar and cream myself. 
I wouldn’t choose the “extremely pregnant lady” since a delivery would ruin my car (or kill someone). However, if the “aggressive vegan” is shooting his mouth or being a little shit, tough. I stop where I stop and I don’t need to talk to the fucker (that’s why God invented headphones).
Did your college hire Nick Van Owen from the Lost World?!
Might I make a suggestion? If you are interested in culling your cream intake, I find soy milk goes good with coffee too.
Hey! The rule is, no calling shotgun until we’re actually within sight of the car. Sheesh, I’m an only child and even I know you can’t call shotgun ahead, or in your mind, or anything. 
<giggle>
I am just picky about what I eat on road trips, McDeath and Burger Death give me the shits, and that is not fun on a long road trip. It is also just cheaper to bring all the food along and not bother getting anything except water or iced tea or hot coffee along the way.
We have a killer recipe for beef jerky - it is easy enough to make to bring along. Way better than the chemical loaded store bought jerky.
Tried it, and the only reason I would cull the cream out is to not conflict with the vegan - I am just as happy with hot tea as hot coffee. As long as my BP meds are working I can do a cup in the morning, otherwise no coffee at all. At least tea is low enough in caffeine to not give me palpitations. Normally on road trips I default to ice water after that first iced tea.
And being sensitive/allergic to coconut, coffee whiteners give me the runs [my normal reaction to palm/tropical/coconut products]
This was pretty much how my decision process sorted out. And if I absolutely have to deliver the baby myself, I can. (Though if complications arise, we’ll be in serious trouble.) Along with other people, it’s the militant, evangelizing nature of the vegan that makes me pick the pregnant woman. If the vegan was able to talk about anything else, I’d probably pick them instead. I also agree with the observation that there are going to be giant stretches of the drive where vegan food simply isn’t going to be easily available (From personal experience: W. Texas, large chunks of N.M, Nevada, and Arizona).
Thank you for helping to plan the route. 
Pregnant woman. I’m vegan sympathetic and have no problem eating vegan meals, but to be trapped in a car with an aggressive, militant vegan who won’t shut up for a long trip, nope, I’ll take the pregnant lady and hope she’s nice.
I like to stop and stretch my legs and check out the rest stop areas, so frequent pee breaks are no problem - I’m used to it from travelling with my dogs.
If she goes into labour, I have a midwife friend so I know all about birthin’ babies (not) and it would make a heck of a good guess what I did today story.
I think I’d probably go with the pregnant woman, unless.
She spends the entire 3,000 mile trip talking about babby babby babby babby babby babby babby babby babby… babby clothes, babby strollers, babby accessories, babby feeding, babby birthing, babby babby babby babby babby…
If that’s the case, I reserve the right to turn around, go back to LA, and pick up the vegan. I can put up with the vegan evangelizing more than I can put up with the babby evangelizing. If the pregnant woman discusses all manner of topics aside from babby, then the vegan can suck it.
The pregnant one. I delivered a lot of babies in my early career.
While I will pit my ability to ignore chatter against anyone else’s ability to ignore chatter, I’ll take the pregnant woman. The route will be planned to connect the dots between hospitals. There will be many rest stops. There will be a cell phone, flares, a labor kit, and a baby care kit, just in case. And towels.
Odd are she’ll still be pregnant when we get there. If she goes into labor, odds are that we’ll get to the hospital. If we don’t get to the hospital, odds are that the delivery will go fine. So there’s a good possibility of things being fine. There’s no chance of things being fine with the vegan with no ability to shut up.
If you can’t deal with the idea that something can go catastrophically wrong, you shouldn’t be planning a 3000 mile car trip.
Do I love the woman? Because if it were my wife, I can’t see how I’d let her go on the trip without me, and if it were one of my sisters, my stepdaughter, or one of my nieces, I’d be much more comfortable accompanying them on the trip than not (unless someone I knew well and trusted were also on the trip with her).
If it were a woman I didn’t know, I’d go with the vegan. I’m confident I can take most herbivorous humans in a fistfight. 
Also, part of me enjoys arguing for its own sake, and this situation would free me of the need to pick a fight.
Gosh, what a badass you must be! If I was driving cross-country with you, I’d only hope some of that Charles Bronson testosterone would find its way into my bloodstream! Please, tell us how huge your cock is next!
If you’ve got a better way of dealing with an aggressive vegan than channeling Charles Bronson, I need to hear it.
I’d just sprinkle some bacon bits into their salad until they got too sluggish to keep yapping.
Hey, not bad.
Try channeling Chuck Norris.