Can I get a rain check?

I'll admit there are a few shows I like to watch on the tele, but I rarely find time to catch 'em and I got rid of my DVR (I know, what was I thinking?). Well, one of those shows that I worship is The Office and yesterday Season 3 came out. I was pretty excited to pick it up from my local Best Buy (thanks for the gift certificate, Kim!), but when I got there it was all sold out. At $32.99 it's a pretty good price and like I mentioned, I had a gift certificate. Afraid that the price would go up after a day or two I thought I would do the "safe" thing and get a rain check. That's what rain checks are for right? I mean, c'mon people, right? When an advertised item runs out of stock you get to come back when they do have it in stock at the same price unless the ad specifically states "no rain checks". At least that's what I've been raised to understand. Correct me if I'm wrong, Mom. According to Best Buy, I'm wrong.

After standing in line at the customer service counter for a good 23 minutes a blue shirt and a name tag that read "Rachel" greeted me with a forced smile. I explained the situation and that I would like a rain check. Easy enough. She went to work pulling the SKU and typing furiously at her terminal. I gave her all the information and the next thing I knew there was a proper printed rain check in my hand. Awesome! I was ecstatic. Then, the unexpected:

"Alright, sir, you're good to go," she said.
"Great! Thanks," said I.
"This rain check guarantees the price, but not the item."
"OK...wait. Excuse me. What?"
"The rain check guarantees the price, but not the item."
"I don't follow [I looked down at the $39.99 price]. Why would this guarantee a price higher than what it's marked today? Isn't the purpose of a rain check to guarantee the price?"
"Like I said, the price is guaranteed, but not the item."
"So you say, but why would I want a rain check for a 33 dollar item that guarantees that I can pay the full 40-dollar price tag later? Why would I do that?"
"I don't know, that's our policy."
"Well it sucks...[I turn and walk away counting backwards from 10 while taking deep breaths]"

America, I apologize for my naivety. All this time I've been believing in something that just isn't true. It's sad that I had to go through this embarrassing ordeal to finally see the error in my whays.