I don't take after-sales rebates anymore. I did once, and it took months and continued nagging, even snail-mail letters, to just get the promised money.
Rebates are one of those big rip-offs in life. I think in all that I have sent in, I've received the money once.
I think it's their way of not selling something at a sale price. They promise the rebate and then delay it for so long that you; 1) forget all about it or 2) simply give up. And of course all this time they have your money.
Anyone interested in this subject beyond the level of speculation and anecdotal evidence may want to research MIR (not the space station but the acronym for 'mail-in rebate') or visit the Wikipedia page.
Surely, in the USA even the Less Government More Liberty faction must be yearning for federal legislative intervention on this matter — or perhaps they are at home oiling the guns.