Because 7 understands all too well what it is to experience a sensory pleasure for the first time. She gets it that the EMH went nuts with the opportunity. She's angry with him, but relates to the experience of existing in one state and suddenly, dramatically being in a completely different state. With your car analogy it would be more like you lend someone your car who has been in prison for 30 years and when they return it to you it is full of the debris of their madness of freedom. And you're pissed off but you also get it.
I remember just liking this episode when it aired, but my favorite voyager moment came when the Doctor and Seven of Nine sung You are My Sunshine. What a wonderful rendition of that song. Over time the episode has become one of my favorites, even though I still don't like the Neelix subplot with the ambassador. It reminded me too much of Liaisons from TNG, and I didn't like that episode either.
Cou-bullshit-ough! Voyager s04e17 Retrospects is how Seven reacts to being violated, full of piss and vinegar, armed to the teeth and never going to stop till there's a dead body where there used to be an asshole who thought they could get the best of her. That's the wonderful thing about her relationship with the Doctor, if something offends her, she can just pull it out or wind back his personality to a point that she didn't want to feed him Klingon in Engineering. Seven could have done horrible things to the Doctor he wasn't allowed to talk about of couldn't remember until she decided otherwise... IT is just a MACHINE and IT does not deserve compassion or mercy, IT deserves to be remodelled until IT isn't an asshole. Not only can't it learn from it's mistakes, but it makes MISTAKES like abusing his FRIENDS hospitality on purpose as a didactic moral play to keep the crew entertained. IT fucks up on purpose, because it's cute and makes the "humans" feel better about themselves and superior... Which is just a logical progression of how Zimmerman described the interactive facilities of the LMH were primarily used to combat spacemadness and depression.
Someone is really well-made but am I the only one who finds it a bit...sugary? I guess it's the nadir for any Doc/Seven haters.