The UK Treasury has cold feet about the department of culture, media and sport’s review of fixed-odds betting terminals, expected to recommend swingeing cuts to the maximum bet. The chancellor is said to be alarmed about losing a lucrative tax stream.

Absurdly, FOBTs, which seduce gamblers to play for as long as they can, are treated in legislation as if they were games of skill. That means players can bet up to £100 every 20 seconds. But there is no skill whatever involved in playing them; only in programming them to extract the most cash possible from players. Recent figures show that adds up to about £2bn a year, which is an awful lot – hundreds of thousands – of losing gamblers. It is also more than half the revenue of the high-street betting chains, and generates £400m a year in tax.

It is not just the speed and ease with which money can be lost that makes these machines dangerous. FOBTs trade on a psychological insight: what keeps customers engaged is less the hope of winning than the pleasure of playing. They are designed to induce a state of “flow”, or “being in the zone”, in which all of the player’s attention and consciousness is pulled into the game, and nothing from the outside world can impinge. It is, while it lasts, entirely satisfying. This is a similar mechanism to that which, in popular myth at least, leads teenagers, lost in their video games, to starve to death after playing for days and nights without sleep or food. It depends on speed of play, and in frequent but never predictable rewards. The knowledge that intermittent reinforcement works better than predictable rewards goes back to the psychologist BF Skinner’s theory of conditioning, and the gaming industry takes full advantage of it. The machines can pay out something on nearly half the spins, without ever losing overall.

Such a tightly circumscribed and rule-bound world has an obvious appeal for those whose lives don’t hold a lot of other pleasures. It is not just the addictive personalities who are vulnerable – even though a US study estimated that there are more Americans who are gambling addicts than survivors of breast cancer – it is pre-eminently people who are poor and unemployed. Betting shops seep along high streets as conventional commerce recedes, but betting shops sell nothing but dreams.

The DCMS review was due in June, and has now been postponed until October at the earliest. The government is considering lowering the maximum stake to £2, a move backed by all the other political parties, including the DUP, on whom it depends for its working majority. The big gambling companies will fight tooth and nail to protect their huge profits. The government should recall a report earlier this year from the cross-party parliamentary group that pointed out that the money siphoned out of poor communities by gambling could be much more usefully taxed if it came from consumer spending, or the income of people in work.

The harm done by the addictive nature of these machines of extortion is not in doubt. There is strong cross-party support to slash the maximum stake from Iain Duncan Smith to Tom Watson, who has offered Labour votes to overcome the resistance of Conservative libertarians. The government has acted before against the indefensible when strengthening regulations on payday loans. There is no excuse for inaction now.