Pay to play (pay for access) is the oldest trick in the book and lobbying is possibly the third oldest job on the planet behind prostitute and fortune teller.
Some conservatives are irked by the fact that Hillary Clinton's foundation has drawn in over $2 billion in the past decade or so. Yes, she claims to be dead broke, but "broke" means different things to different people. At that's how the Clintons see it.
Hillary, mindful of the limitations of a president or cabinet officer getting direct bribes, decided to front-load them as the Democratic Party's only apparent candidate for the US presidency. Conservatives are angry. The cynic in me would suggest that is because they (a) didn't think of it first and (b) have a field of twenty candidates, each of whom is dragging the sack for money.
Hillary Clinton has a large rolodex and she is clearly a rain maker as is former President Bill Clinton. If you want them to fly somewhere for a day, you need to hire an executive jet (whether it's Bill or Hillary, it's good manners to hire a 'hostess' or two for the trip) and fork over another $10 million. The presence of Team Clinton can often make the difference between winning and losing business.
President Obama has the "advisory council". Joining will set you back $500K. It brings access. If you're George Soros, Obama calls you, you don't need to call him. And that's how it works. It worked the same way for George W. Bush (I'm not on my high horse).
At this point, I wonder if it can work any other way.