He didn't want to admit he was wrong or take responsibility about the money. So, he could not let the conversation end there, with you looking reasonable and him irresponsible and unable to justify his position. He tried to provoke you into snapping at him. Then he could say / imply / believe that you are a crazy lady who nags and flies off the handle about the most inane things. Thus, everything you say is crazy, inane and should be ignored.
That could be called deflection - deflecting from the issue you've raised into a 'but you do something bad too', 'two wrongs cancel each other out but anyway yours is worst' fest.
It could be called 'having to have the last word'.
It could be called exhausting twattery and why would you live like that?
But, I'd say there could also be an element of this having been an inopportune moment for you to choose to start this conversation. First thing in the morning (are you both morning people?), while doing something else, in public, on your way to doing something else (work? which perhaps he was thinking about at the time?).
So, I think you need to choose better times to instigate conversations about family finances, when you're both calm and available to focus on the subject at hand.
It sounds more like you were expressing frustration at him, in a situation that could only leave him stewing, than seeking to have a sensible discussion with him, that might lead to the desired outcome.
So my question to you is this - is your desired outcome that he changes this expenditure? Or is it to express your frustration and make him feel bad, temporarily? Or perhaps even a signal that you're considering doing so permanently by leaving him?