Shady as Fuck.. buyer beware when using Best Buys reward zone certificates...

Firstly let me say that I have been a huge fan of Best Buy.  I purchase the majority of my blu-ray and electronics from there and I have always had good service.  I am very disappointed though in their new reward zone redemption rules.  It works like this...you accumulate points with your purchases and then they send you redemption coupons.  You print them out and take them to the store with you and they scan it when you check out and it takes whatever your value is off of your bill.    Clearly, they can set this up any way they choose since it is something they are giving you.  Last week I purchased two cellular car phone chargers and two movies.  I handed them my $20.00 coupon and they took that amount off of my total. My bill total was $80.00 and they took off the $20.00 from my coupon.   I left happy.  Well it turns out I didn't need 2 cell car chargers since my old one fit my new phone.  So yesterday I went back receipt in hand to return my $27.00 unopened charger.  This is where the shady as fuck part comes in...  when the cashier began the transaction he did his level best to convince me to shop for something else..I said I didn't want anything else today..I just wanted a refund.  He mumbled on about me not getting the full amount, and I didn't understand. So he went over the receipt with me and showed me that now when you redeem your coupon it takes a portion off of each item instead of off of the total. So for my $27.00 car charger that I paid cash for, I would only receive back $17.00 and the $6.? would go back onto my reward zone, and I would have to drive home print it out and come back and use it in order to get that money! Not only that...but the coupons only print out in $5.00 increments..so I could not even get my full amount back until I accrue more purchase points. They owe $6.? and I can only get back $5.00.  As I stated earlier..they can set this up any way that they choose, but they should have informed me at the time of purchase how it works.  I would then have used my coupon only on the movie and purchased the other items separately.  What they are doing is not illegal but it sure is underhanded and shady to say the least. I am sure whoever came up with this idea either got a bonus or a promotion.  It clearly fucks over the consumer and forces you to have to shop to get your money back.  I am so angry...that I am one, blogging about it, and two, going to print out my coupon..return to Best Buy and find something that is truly that amount, and then, guess what...I will start looking for alternatives to purchasing there.  Amazon has good deals on Blu-ray, and there are other places to purchase electronics.  I hope it was worth the dollars they will lose by being shady and taking my money!!!!!