Yeah irresponsible people do. But it's not necessary to bet the farm to make a living. Although it's certainly easier to eke a living off a $600k bankroll than a $50k

Many hedge funds and active traders do this every day. Maybe they're irresponsible, but they're the norm.

It’s different when it’s someone else’s farm.

If you set up a stop loss you could make it impossible to lose a huge enough amount on a single trade to wipe put the profit on your prior ones.

all stop losses do is create an order when a certain condition is met (e.g. last trade price is below X)

there's no guarantee it will be created immediately, execute at all, and if it creates a market order you might very well not like the price it does end up executing at

“Stop-loss” orders don’t work perfectly. If the entire market has gone South, you can lose a lot more than your stop-loss says.