I don't really consider myself stupid, but when I picked my iPad up last week from Best Buy I really wasn't given an opt out. I argued that there was no need to do the "activation" or run my credit, and I even had to talk to a manager, but was told it was new policy and my only other option was to purchase a WiFi only model if there were any left. Personally, I didn't really care about the credit check, I was told it was needed to make sure people with balances owed to AT&T or Verizon weren't allowed to buy/active an iPad (BS I'm sure). The part that bugged me was the posibility of being put on a post paid account (something I knew could be fixed but didn't want to hassle with). That's why I kept telling them I didn't want to activate the 4G and wouldn't give them a date of when I wanted it activated. Just kept telling them the dates would vary so don't activate it.
So Best Buy basically lied to you. I would look for another iPad, buy it, and return the Best Buy version