I joined BMG back in the early 80's when for classsical it was called the "International Preview Society". A promotion back then I took advantage of gave me 2 free (single) recordings a year, free for life, as long as I maintain my membership. 20 years later and I still get my card from them for what is now 2 CDs free per year for life. So I guess I have gotten about 40 free recordings this way.
I have also gotten a few free CDs from their Music Points system. Once a memeber my advice is to wait for the sales, like buy one, get 3 free; or 70% off (the current sale).
Their online site has actually been up for over 3 years. You can deny the auto purchases online as well, instead of the cards.