iTunes annoyance

I was in Australia for a month, and spent much of my time flying around, listening to my iPod. When I'd come across a song that sucked, I'd rate it one star, thinking when I got home, I'd cull those songs from the library. No such luck: on update, iTunes updated all the ratings with the ratings from the library, so I lost all the information I'd put in over a month.

Why even offer the ability to rate a song on the iPod then if it's only going to be over-written? What possible reason would that functionality exist for? Even if you want to stick with the library if the rating on the iPod changes, shouldn't any rating be better than no rating?

And if it's not supposed to work this way, how hard of a test case is that?
1) Take unrated song
2) Rate it on iPod
3) Hook up iPod to computer for update

Did song get updated with new rating in library? Y/N

Why does Apple have this reputation for amazing quality of product and design when they can't figure out simple crap like this for their most-prominent, supposedly most-usable product?