Same here. Didn't know they are ripping off remastering. It is very surprising, considering the fact that most of the Proper sets I've listened to were very inconsistent sound quality wise.
Personally, I love Proper Boxes. they are bargain priced, have desent booklets and discography info, and sometimes they contain invaluable stuff. The Wardell Gray set, for example is great and it offers most of Grays unforgettable moments, including some rare airchecks.
I won't even go into the 50-75 years debate. suffice to say that in Israel, as well as in the EU, the 50 years period is the law. That's good enough for me.