@hastalavista Interesting one. Your assumption that 'people on the exchange with me (apart from other matched bettors) are at minimum fools that I'm taking advantage of, and at worst, victims of gambling addiction'; raises some questions.
Questions to think about...
Half of all adults in the UK engage in gambling. A tiny percentage are gambling addicts. Most are people who enjoy it responsibly as a leisure activity and have fun doing so.
Should adults be able to choose to enjoy participation a legal, regulated, leisure activity with their own money? Why is this unethical?
What causes gambling addiction? Gambling, alongside the use of substances like drugs and alcohol and even activities like shopping, sex, extreme sports can become an addiction when its use becomes compulsive and spirals out of control. People become addicts because they have addictive personality types, mental ill health, are high risk takers, or have low impulse control.
Should we refuse to visit or work in pubs and restaurants because some will become alcoholics? Refuse to work in supermarkets because some will become addicted to overeating? Ban extreme sports? Sex? Shopping? Too much internet browsing? Social media?
Betting and gaming duties raise £3.5 billion a year in revenue for the UK government - worth about £124 per household. Should we stop collecting this and charge every household an extra £124 each year in tax?
Do you pay into a pension? How is it invested? FTSE 100? If so, you already have shares in the bookmakers by default as they are listed companies. How is this any different or more ethical?
All activities in life involve some risk. Adults are mostly free to choose their own level of risk in leisure activities, provided it is legal. Alongside this, regulations are in place to protect the young and the vulnerable, and it's why regulatory authorities such as the Gambling Commission exist. Controls and checks could perhaps be greater, more effective, better enforced in many walks of life, but the UK Gambling sector is one of the most highly regulated markets in the world.
One individual matched bettor alone cannot police or take responsibility for the risks of other adults in their entertainment choices.