Jobs and money circulation

If the job that someone is doing is not directly contributing to the sum total of the planet's and humanity's health and happiness, the only point of them doing it is to get money and it doesn't make sense to make someone do something that we don't really want done just so they can get money. We should preferably pay people to NOT do what we don't want done.

We could pay someone to build a wall and someone else to knock it down again. That's work for two people, so good, right? Yet obviously utterly pointless. In real life the contradictions aren't so obvious, but why pay someone to sell cigarettes and someone else to stop people smoking and another person to try to cure the ilness that smoking causes? Why make someone give up caring for their children to go and work in a fast food shop that sells unhealthy food to other children to earn money to pay the childminder they need because they're at work?

These loops are everywhere you look. Perhaps you go to work to earn money to pay for the car you need to go to work in. Perhaps you work in a shop. You need people to come in and spend money in your shop so that you can get money to spend in another shop. There's a finite number of shops, so eventually the money comes back to where it started.

You only need to hold on to the money that you need to survive long enough to purchase what you need to survive, then the money becomes someone else's and they use it for exactly the same purpose. But of course in this system not everyone has all the money they need and some have more than they need. If you don't have enough money to buy a house outright (as most people don't) you have to borrow it. You could borrow it off people who have money to spare, or you could borrow it off a bank, but either will want interest. This way the lender finishes up with more spare money and the borrower less money than he/she started with.

Don't think that the bank lends you money that people with spare money have lent to them. No, for the most part, the money that yo borrow from the bank is created specially for you out of thin air. This is how savers can have instant access to their savings whilst people can still borrow. For each loan that is made, there's more money in total, and because every loan has interest on it, the total amount of money owed is more than actually exists.

People aren't going to give their money to someone who needs it (generally speaking). They might lend it (at interest) or they might buy something. Therefore people have to go to work to make stuff for people to buy, so they can get money to buy necessities and pay back their loans. This leads to there being people whose job it is to convince people to buy things (advertisers), all just to keep the money moving.

Most of us have to work to survive and pay off our loans, but does money motivate us? It can't because it's useless unless you buy something with it. You can't buy happiness (which is what you really want) so someone tries to persuade you that you will be happy if you have the thing they want you to buy. They have to do that to get your money, but your money is useless if you don't spend it.

How does this make any sense?