I believe (many of) the machines in question are fixed odds betting terminals (FOBTs) where the outcome of every game is random. (The odds are of course weighted in the houses favour, but some of the games, e.g. video roulette, have a return to player as high as 98%). These would generally be category B and be found in betting shops and Adult Gaming Centres. It's these machines to which the article is referring.
Fruit machines (usually category C or D) found in pubs and FECs (family entertainment centres) are almost always compensated and behave in the way you describe.
In answer to a point further up, the maximum *steak* (not payout) for a category B2 and B3 machine was recently lowered from £100 to £2 (£5 for B1), which coincided with many of the B3s finding their way from betting shops to Adult Gaming Centres (industry speak for high street arcades and that 18s only bit usually found at the back of amusement arcades).
Interestingly I noticed over the summer that on the B3 FOBTs roulette and games like it (RTP 98ish%) were removed from these machines in favour of other games with a return to player around 90%.
(Source: I regrettably spent the last year managing a sea side arcade. I got out in the end because I came to truly hate the industry).