You can just look this up, it's not a secret. Median total pay, including tips, in the US is $32k for waiters. In France, it's €22k. The UK is £23k. Even factoring in health insurance costs — ~4.5k/year for an Obamacare plan — waiters make more in America.

Waiters in the US make significantly more than their British and French counterparts, due to tipping: the US minimum wage is lower than the British and French minimum wages, and despite American waiters being paid at an even lower hourly rate than the US minimum wage, they end up making more due to tips, performing the same job.

The upper 25% of waiters in the US make over $40k a year. Your 95% estimate is very off base.