I placed my first order from swf.com that I had in a couple years about 2 months ago, and I've had been getting the $10 credit emails the whole time. I also got the one yesterday, and like I said, it's been a couple months since I ordered. So... I think it's just a cooincidence that they come right after a particular order.
Yes, you still get the free item from the frequent customer program when you use a credit. For those that are not frequent orderers, SWF.com has a frequent customer program that places you in different tiers depending on the total amount you spend with them since you establish an account. I'm in the top tier and it gives you a $20-$30 item with every purchase. It's always a choice of a few items in a given price range, and usually it's enough of a selection that you can find something useful. In my case, the free item is valuable enough to offset the shipping cost.
I almost always get a cleaner shrimp.
The $10 credits come often enough that if I can just wait until the next one comes along to order, it's not usually a long wait. Yes, the minimum orders are there, but it all figures in with shipping costs, etc. Some of us may remember back in the day when minimum orders were $80. SWF has been pretty good about passing along shipping savings onto us and ordering here has gotten a lot cheaper and easier over time.
The $10 is only "not a deal" if you choose to look at it like they are forcing you to buy something. You didn't need the credit to get you to make an order in the first place, nobody is twisting your arm to make another order just because you have a credit. If you don't need anything, let it expire and don't worry about it. That's what I do... all... the... time. Not ordering or not meeting the requirements to take advantage of the deal costs you nothing more than regular prices you are used to paying do anyway.
I don't want to sound draconian... and not saying that anyone here does... but if someone has a beef with swf, you should email them or at least take it up in the ask swf.com forum. I'd be nice if we all make sure we aren't using these free boards to air our grieveances with the company that provides them.