>If you make it free, then everyone will choose the fastest one.. which means it will no longer be faster. So in order for time saving measures to work, you have to require selectivity.

Or you can increase staffing.

> The idea that this is meant to put tranches of society on display is ludicrous.

It may or may not be meant to put it on display, but it shows it for what it is. People who can afford to pay to save time get prioritized through public infrastructure, and people that do not pay have to wait.