The question isn't whether lossy means "lossy," the question is whether lossy means "audibly different." Years ago Stereophile published an article called "MP3 vs AAC vs FLAC vs CD" which was really meant to argue for the superiority of lossless compression, but actually does a pretty good job of explaining both subtle differences between AAC and MP3 at the same bit rate and how high bit-rate lossy encoding pushes artifacts down to inaudible levels. You can put up an AAC/MP3 frequency graph compared to a FLAC/CD frequency graph and have it look absolutely horrifying, until you notice that the junk on the AAC/MP3 chart is all at -100db and below. Unless your listening room is an anechoic chamber, you're just not going to hear it. (In most cases it's probably below the noise floor of your reproduction equipment.)

I often think I can hear the difference between lossless and lossy, but IIRC, the last time I did ABX testing on that, there was only 1 out of 5 tracks I tried where I could tell the difference at a statistically significant rate. (And I'm not sure I'd be able to repeat that.) The best argument I have for storing music in FLAC (or ALAC or some other open lossless format) is analogous to the argument for storing images in a lossless rather than lossy format if you have the space: if you ever have to transcode the file to something else, start with the highest quality possible.