There's a fundamental power imbalance: if you do this to any service, they will likely ban your account. So the monetary reward has to be enough to merit moving all your data and workflows off them in advance and never using them again.

^ This.

I naively disputed Steam not honouring a refund (it was for about 0.5% of what I've spent with them up to that point), a couple of £pound at most. I'd paid by PayPal and as Steam refused to abide by UK law (Consumer Rights Act says broken stuff has to be fixed or refunded), I raised the issue with PayPal. I expected Steam would refund me, instead they did not dispute that they'd unlawfully failed to refund me, so PayPal - Steam's provider - cancelled the charge.

In response, Steam 'limited' my Steam account - effectively closing it temporarily. Now it's limited so they won't use PayPal to sell me anything now, so I haven't bought anything from them since [I have cashed in CS skins, and used that cash to 'buy' games].

It was an interesting lesson in 'might is right'. PayPal were able to refund the transaction because Steam want them and had no argument against the refund. Steam were able to cut me off because this appears to be a loophole in UK consumer law - sellers who break the law can just dismiss buyers who ask for refunds. Lesson learnt.

From Steam's point of view, they pissed off a customer and probably burnt 30mins-1hour of support time in answering my requests, way more than the cost of the refund. But selling games, which I later found Steam knew was broken, and then not refunding because I had the tenacity to try and fix it - meaning that the game sat open for longer than their auto-refund time - is not on imo. Petty of me for sure. Crap of Steam too.

No that's not how that works. This stuff is a non-event. You refute the balance, they have a period where they can defend their claim (8/10 times they don't), you get your money. This is a very basic transaction that happens every single day to every major company. "Banning" you costs more than your refund and has additional legal risks.

I know being helpless against tech companies is a major trope in these comments but this is basic everyday transaction stuff. Plan on being on hold with your credit card company but not being a central target for a trillion dollar AI startup because you asked for a $100 refund.

They won’t ban you for going to small claims court?