I grew in a very non-mechanical family--cars were always taken to someone to fix. But Mr. Outlier had a proper upbringing, can fix anything, and does all the work on our cars and motorhome.
He showed me what to do at home, and while still there, I loosened the cables a little and tightened them back up, to make sure nothing was stuck. And I took that wrench with me to Costco.
And yes, nobody offered to help. I'd like to think that I was exuding such confidence that people didn't want to run the risk of insulting me, but I really do think it has more to do with women becoming invisible at a certain point. When I took the old battery right back in to get the core charge refunded, I told the kid, "I changed it myself in the parking lot!" He just looked at me.
That same trip, I bought one of those mattress in a box things. In the store, I managed to get that monster onto one of those flatbed carts with nobody offering to even keep the cart from rolling as I tried to get the mattress onto it. I eventually lodged it up against the end of a shelving unit and pushed the mattress over there.
And I wrestled it into the back of my car by myself. As I finished, a lady walked by and offered to take my cart to the corral, but I was going to need it to take the old battery back to the store. After that, it was my completely unmolested battery time.
It's funny because I'm always the first person to offer to help. I'm the one, in a full restaurant (back in the day, of course), who will notice someone in a wheelchair trying to use the door and jump up and get it. I like doing shit like that.
Actually, now that I think about it, Mr. Outlier's and my second date was to play pool. I got there before him, and there was a guy in the parking lot who needed his battery jumped but didn't have cables, and neither did I, but I told him I was meeting someone who probably would. So our date began with Mr. O joining me and another man to jump this stranger's battery.
At least he could never claim he wasn't warned.