Thanks @emma-h! I'm glad the battery jump folks turned out to be good people, too. I'm pretty sure I would have vibed them out if they weren't, but still, yeah, I didn't want to end up camping right alongside them. And then whipping out my portable jumper like, look, hehe, I had this all along but no you can't use it!
Just keep being you - the length of your fingers don't define who you are, that's up to you to decide.
Lol that would be a terrible way to end it for sure and you'd feel really shite about it too.
It's always good to try size the situation up before getting involved too much so I think your course of action was wise.