DH and I own a small business, hobby and game store. From what I understand if you shop at a small business with an amex you get the amex rebate. Here's the kicker though, amex is the most expensive card to process for a small business. We pay about 2% per credit card transaction fee, amex is closer to %5, so by amex encouraging people to use their card at small businesses it's almost hurting us more than it is helping us, (us in the small business collective), our store doesn't even accept amex because of the ridicuolous processing fee for us.
So what we've been telling people who ask is to shop local any and everyday you can. Don't just use small business saturday as your reason. Our store has had a special going on all month, spend $30 get a holiday envelope, bring it back sealed in Dec and we open it. It can be anything from 10% off to a $100 gift card.
Small businesses can't compete with BF so we are thankful for amex recognizing this, we just want customers to be aware of what it actually means to us. Thanks for shopping local!