The only reason that I can think of is because we humans; as a species are innately greedy. And our greediness has no limit when it comes to power and money.
Today, we all use more utilities than required and spend more money than actually required. Some examples are -
  • We don't need the processing power we have currently in our hands in form of smartphones, we certainly don't need titanium in our phones
  • We don't need concrete everywhere in our cities. Just planting thick trees along sidewalks would do wonders
  • We don't need our housing materials to be made of all unfriendly materials, plastic, laminations, glass, marbles, stones etc.
  • Ohhh and, billionaires and govts funding space programs when manual scavenging is still a problem in this world. Think about hunger, war, poverty, illiteracy, poor health among others. It just breaks my heart.
  • Plastic bottles hahahh, omg. Who had thought of selling water inside plastic?
the list will go on and on if we carefully examine the things we use on daily basis and things we discard without even paying heed to repair it.
So, ultimately the economic growth we are seeing currently is net-negative growth for humanity IMO