I'm not saying I don't use rebates. I keep track of what rebates are paid and which are not and I only have one unpaid rebate and it wasn't on electronis gear - it was a $2 rebate from Long's and I won't be bothering with any of theirs again.
You do have to understand that you're loaning them money and consider the time and effort to mail the stuff in when you evaluate the rebate and you're possibly paying sales tax on that free loan too. But I've eventually gotten all of my rebates (other than that one).