I sometimes buy mp3's to try stuff out. In the case of this box set, I was able to sample an entire track for 10 cents. This has helped me to confirm or avoid many recordings in the past so I do it. If I love it, I buy it. If I don't, I spend the money I saved elsewhere.
I agree that the bitrates should be much higher. One of the things some sites are doing is offering higher bitrates for more money, which is better, but if you ask me, 192 should not be the minimum. I think 320 should be the minimum, as it's pretty damn hard to tell the difference between this and the original IMO.