You may not directly participate in capital markets but institutions around you that society relies on do. They do so to secure operating cash, loans, buy or sell insurance, etc. When people participate in capital markets they do so looking to make a profit or to purchase some utility, ideally these people have done some research about their trade before firing. Market makers compete for the right to charge you a fee (the spread) to make that transaction. You’re paying a fee to sell them risk (the risk that you’re correct with your opinion). Collectively this adds up to information exchange between all parties becoming less expensive: more participants on either side of any trade, smaller spreads, etc. Less friction.
Options MMs are more or less directly buying and selling insurance.