At my last job I had a 50% match, so if I put away the $18,000 max then I'd get another $9,000 added to it. A friend of mine worked at a hedge fund and got a 200% match, that is, if she put away $18,000 then her employer added an additional $36,000 to it. Their rational was that the IRS lets them do it and it's an easy way to transfer wealth from the company to the employee so why not do it.