Which is exactly how I would react. Except that I would be really angry and say something like, "You better drive that thing back to the car dealer faster than I can run, because if I catch up with you, you are going to need medical care." Even if we were sitting on piles of money and could afford 30 brand new cars, I would still be majorly ticked off if my husband bought one without discussing it with me. Married people, they should discuss things.
Which is why I got the itch in Sunday School recently to raise my hand amidst all the glowing comments about Eve and her "bravery" and "wisdom" in eating the forbidden fruit and say, "Don't you think she should have discussed it with her husband first?" I mean, no matter how much foresight Eve may have had, no matter how convinced she may have felt that eating the fruit was the right thing to do (though, frankly, "the serpent beguiled me" doesn't exactly sound like "I know what I'm doing here."), the fact remains that she did something that would drastically affect her husband, their marriage, and their family -- forever -- WITHOUT DISCUSSING IT WITH HIM.
"Adam, honey, guess what? I ate this fruit and now I'm going to be kicked out of the only home we've ever known and consigned to a life of sorrow and pain and hardship. I hope you're okay with that, because if you want to stay with me, you have to eat the fruit, too!"
Honestly, it doesn't matter how right a decision turns out to be if the way you go about making it is all wrong. You don't get to do whatever you want to do (or even what you think is "best") without taking your spouse into consideration.
This doesn't mean you need to talk about every little thing (obviously). A dollar for a candy bar is probably immaterial and it's not like you need to call up your spouse any time you want to go out for lunch or get your hair cut (unless doing so would be a burden on the family finances - in which case you do need to run it by your spouse first) but you don't get to make the decision to have a baby or take a job or buy a house without some serious discussion. You don't get to make life-changing or bank-breaking or debt-incurring choices without asking for input and approval from your spouse.
If you're truly a team, you both need access to -- and equal say in -- the game plan. Especially when it concerns those life-altering apples.
Otherwise they might come back to bite you.