Because I assumed you'd understand the depreciation of the asset is a lot less than the appreciation on your investments or cash that you can do in the other scenarios. The entire point is its offset. Also that's not a business asset description, thats just normal life??? WTF buys a camera and doesn't offset some of the cost doing their mates wedding? You're not thinking rationally if you think using the credit system is comparable to a roulette wheel. You control its use. You can just clear the debt if its interest free, its not grown or changed. The credit system is designed around returns for people who can't afford something at all. It's utterly predatory, but if you financially are entirely above the risk of paying interest its just a lot of flexibility in preserving your cash capital.

Moral aside of shooting mates' wedding and charging for it(!), but as soon as you use equipment to earn it's a business/side gig. You may not like it but I'm sure tax authorities of any sane country will disagree with you.

For the rest I actually agree with you and think credit system is predatory and that if one can, one should take advantage of it. Just that buying something on credit because want, and using that something to earn money are two fundamentally different cases.

Why is it a problem if it’s a business or side gig? In the UK at least that just means that you need to report the income on your tax return if it’s above a certain amount. It’s not difficult. I’m not sure I’d describe countries that make you do more than this as ‘sane’.

Dude what world (or country) do you live in? Im in the UK and everyone has a £1k self employment allowance, that gets you quite a nice camera! Filling out the return is trivial.