This is exactly the gotcha. You paid for a service. The outcome isn’t guaranteed.
Even if your app is successful, you still have to pay the programmers. Even if you sell the building, you still have to pay the construction crew. Even if you're packed during dinner service you still have to pay the chef.
None of these scenarios are painted as a pyrrhic victory because you had to pay the people who made it possible. All those people are generally paid hourly too. Is it because a good lawyer will bill you $400/hr? Is it because those generally have a lot more upside financially than simply winning a court case?
I think it's projecting anger from spec attorneys taking 40% of personal injury judgments, or class action attorneys making $50 million in fees when the people affected get checks for $8.72, but neither of those apply here particularly when you're paying an attorney $75 to send a demand letter template on their letterhead.
Yes, that's the issue. He's poisoning the well. They get paid, but they aren't on the clock for $500/hr the moment you step in their firm.
I imagine consulting a lawyer is also a lot cheaper than preparing a case to sue for.