In some jurisdictions you have to show up to small claims yourself though which prevents some third party from just handling it. Makes sense since the idea behind small claims is to keep the legal costs low enough that you actually have a chance of recovering smaller sums without paying more then what you will get.
You could win that case with very little evidence. Merely the written contract, a photo of the loose antenna (or the antenna itself, if the installer left it behind instead of installing it), the statement from the installer stating that he couldn’t complete the job, and the bills for the service that you couldn’t use but that you have had to pay up to that point. That’s all paperwork that you should have held on to anyway, at least for a few years.
There is the case of ignorance, where a person might not know about small claims court, let alone how it works and what it does. Then there is the case of an increasing number of forced arbitration clauses. Then there is the fact that companies wishing to not get swept up in a wave of small claims will reach out and try to fix the problem if they do actually have a case they think they might lose, further preventing more people from talking about it. And small claims court may ‘only take minutes to resolve,’ but that small length of time would only happen once you are actually seen in court. Before that, you’d need to - file with a clerk (meaning, spend time learning what you need to file, where you need to file it, etc.), - serve the defendant (which costs money and time), - arrive at the court in the morning for roll call, - wait a few hours until you and the defendant are actually called (if they showed up…, which if not expect to come back after serving them again).
This is not a ‘trivial’ task, and all the while the company that scammed you already had your money. As a large company, you can arbitrage the profit of this shady behavior against the risk of someone actually going through all of the steps.
Besides, it’s easier than you pretend. The form you have to fill out is literally two pages long. The costs and filing fees are minimal, and they’ll even waive them if you ask. You can email your local sheriff and have them take care of service, or do it by mail. Yes, you will likely spend more time waiting in the lobby (more likely the hallway in the basement, but whatever) on the day of your hearing than you will spend in front of the judge, but what more could you possibly want? The process has been made literally as simple as is currently feasible.
If a company sends you a $2 check ten years after they recognize a profit from defrauding you or lying to you or harming you, that's not a punishment, and is certainly not an incentive to not do those things.