Re: Lost me here...
Your post is ridiculous.
Most think tanks don't make huge money. Nobody is retiring to the Bahamas! Most of them can't even afford to fully staff themselves.
This kind of lazy-thinking, accusatory, bull-shittery is as much a reason that politics is in the state it's in as arseholes like Trump. Impugning people's motives for shits-and-giggles.
Do some people go into the political realm for bad reasons? Of course they do. Do all people who go into politcs do it for bad reasons? Of course not. Get a grip!
Sure think tanks have biases. But mostly they're known and that's why they attract the funding they do. Which means it's much less of a problem. Especially if you've got a vibrant mix of different ones.
Because they're also vitally important. Most political parties are also under-funded. The US is unusual in the vast sums they spend on politics. But even there, most of that cash goes on campaigning. The boring slog of looking at policy is mostly left to government. Governing parties are usually too busy - except for immediate policy work where they use government, and the opposition are usually too poor.
So think tanks perform a useful role in a weird no-man's land.
Not that it's not subject to corruption. But it's a space where useful thinking can also happen.
Look at Greece for a counter-example. Because London has a huge political scene, when Gordon Brown was indulging in a few shennanigans to keep things off the UK balance sheet (like Network Rail, PFI etc.), it was widely covered. Lots of policy wonks of all types look at the politics and economics here. The Greek government managed to run a 10% deficit for several years, and just lie about it. And nobody noticed. And because they don't have the kind of non-party political analysis going on, nobody spotted it, until it was disastrously too late. That, and being in the Euro, then doomed them to at least a decade of a depression as bad as the 1930s.
Outside analysis of policy is good. Even if flawed.