So the business should be: today I officially launch it, the next day, profit start rolling in
This is really a skewed way of looking at business modules (or to a greater extent, life in general).
The business concept is feadible but does not conform with @OP requirement of non-perishable good.
If it were that easy, there won't be poor people anywhere on the face of the globe.
The anser for this is quite easy, because they don't have capital to start with their business, they have the capital but lack knowledge, they have both the capital and knowledge but lack motivation and the worst is bein plain lazy.
For every business to thrive, there should a sowing period which expectedly will take some months and then the harvest season. It's even a law of nature that we don't plant today and begin to reap immediately. So, why should business or investment be any different? If you keep this mindset, you will be easy prey for ponzi schemes.
In a marketplace where the goods are food, the sowing period is very short and it does not take a day to see profit. Like in a humble local eatery, the sowing period is around half a day and the reaping period is the other part of the day. It is faster in a wet marketplace where the owner spends money renting the place, buying goods to sell and at the end of the day, they get profit after selling all their goods.