Generally, minimum wages are lower for tipped professions than non-tipped for this reason. Assuming you're talking about Seattle, which is the only place I could find with an $18.69/hr minimum wage, tipped employees make $16.50 in comparison [0].
In Seattle, waiters at many local restaurants and bars anecdotally seem to clear about ~$80k/year, so the minimum wage is kind of moot for most of them. I have several friends that work in the industry who have strong opinions on the matter.
The tipping issue in Seattle isn't about a living wage, they already have that, it is about maximizing their income. After all, who doesn't want to maximize their income? The economic structure and dynamics of it are fascinating. What proponents of "no tipping" schemes fail to recognize is that it is against the interest of employees in many cases, even if it is often positioned otherwise.
[0]: https://www.seattle.gov/laborstandards/ordinances/minimum-wa...