Actually, the negotiations appear to be have been just as protracted as with Hachette.
(Maybe longer since Hachette wasn't actually negotiating until S&S signed *their* deal.)
Reports are they've been haggling since at least september, maybe earlier...
The key difference is the HC negotiations were done quietly and professionally (until very recently) with no public whining, full page ads, or leaks to biased reporters. No public campaigns by country club millionaire authors or press releases about going to Amazon's board or the feds. Just two billion dollar businesses negotiating a deal for retail products.
Kinda like razors or toasters...