At most places, management positions--especially high up the chain--have a significant sales component--the most notable exception is low-level operations managers (foremen) whose job it is to oversee production workers and the like.  Other than that....

* The CEO, as the most visible "face" of a company, is its chief salesman.  His/her primary customer is the investment community (Wall Street, VultureCapitalist''''''s, etc) rather than users of the company's products and services; however the "sales" function of the CEO is the one job the CEO cannot delegate.  (Many companies delegate the actual running of the company to a COO; though in many cases that's a sign that the CEO is about to be fired).  One notable exception these days is Microsoft, where SteveBallmer is CEO but BillGates still the most visible face.  One wonders who would win a power struggle between the two, should it ensue?

* Many "large" deals between a company and it's customers/vendors (especially customers/vendors with high strategic importance) are negotiated between corporate officers (usually at equal rank/stature) rather than between salespersons and purchasing agents.  This is especially true if the deal will be on non-standard TermsAndConditions, is for large volume, requires customization, etc.  IBM was well-known as a master of this--if you didn't give the salesperson in the blue suit the deal, his boss would call ''your'' boss; his boss's boss would call ''your'' boss's boss, and up the chain--until some career conscious higher-up, realizing that NobodyEverGotFiredForBuyingIbm, took the deal.

* Many companies desire to know lots of details about the operations of their vendors; functional managers are often used both to perform the assessment (on behalf of the customer) and to represent the vendors' operations.

* In most companies, getting promoted up the management ladder requires a fair bit of self-promotion skills.
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I am not sure of the exact meaning of "sales" as intended above, but I will note that in any leadership position, one needs to convince other people to perform work.  Even when one has direct authority over others, it is far better to sell an idea or approach to them, than to just order them to do it.  When working with peers or superiors, it is crucial to learn how to "sell" ideas.

''Sales means what you think--the art of persuasion.  (Which is, of course, an important and necessary part of the other definition of sales; the art of getting customers to part with their money for the mediocre products and/or services that you have to offer).'''