Because my 'stuff' is made of finite resources.
I believe climate change is probably real and probably man-made, and that the biggest culprit is that we in the West use too much stuff. I see a problem when coal is dug out of the ground a few hundred kilometres from where I live, shipped to China to power factories making consumer goods to be sent back to Australia, only to languish in the back of a cupboard or end up in landfill. The coal will run out. The oil to power the ships will run out. The oil to make the plastic will run out. The phosphorous to make the fertilisers to grow the cotton will run out. The rare metals that go in your phone will run out. But if we start slowing down our rate of consumption, then maybe they won't run out quite so soon.
Because 'stuff' costs money.
At the moment I'm home raising small children full time, and plan on keeping my focus on my family as they grow older. I don't want to feel compelled to return to work to earn money to pay for things we don't need. And the money we do have should be going to things we use, not things to fill the house, and to those who are less fortunate than us.
Because everyone who has contributed to the production of my 'stuff' matters.
The things that I own didn't start their life on a shop shelf. As a Christian, I am called to love my neighbour, which I understand to mean everyone I have a relationship with. This means my children, and making sure they are able to grow up with the same great living conditions that we have now, and not jeopardising that by selfishly having whatever we want whenever we want it. It also means the people who produce my stuff. It's not really fair that I have cheap consumer goods if the people who have made them are being paid a pittance for their work just so that we can have more. It's also not fair if the growers and factory workers are working in appalling conditions just so that I can have more.
Because less stuff means more time for the things I love most.
Less work to earn more money to buy more things. Less time keeping a huge house clean and a mountain of possessions tidy and organised. More time with my family. More time doing things I enjoy.
Because I don't need it all.
Before, I used to think I needed a lot of things. Now, I realise that I don't need half of what I think I do. There are only 24 hours a day, only 7 days a week. Only 365 days a year, and only about 80 years to live. I can't do everything in that time.