For us, sports is a recreational activity to alleviate work stress. However, if you apply the lessons learned from playing sports, you'll learn the board room and the basketball court have lots in common.
Self-imposed discipline with a bent towards results rather than "creative" and sustainability spending is unfortunately not the norm in the marketing industry. But it is increasingly the practice of these tech companies.
While traditional marketing chases vague notions like "branding" and "mind share," growth hackers relentlessly pursue users and growth -- and when they do it right, those users beget more users, who beget more users.
While I do believe that the best marketing in the world can't help a bad product, and that marketing a great product will make growth a lot easier, user acquisition tactics will probably always be necessary.