I have been involved in the hotel and catering business from washing up(a VIP job, by the way) to general manager, from childhood for some 70 years.
This wretched question arises time and time again.
The staff actually serving the public are traditionally paid at a lower rate than the backroom staff.
Things have not improved over the years because of the massive build up of competition, and therefore a related drop in gross profits, and so things are not likely to change on the staff wage bill.
One thing I do know, that as a trainee I was very thankful for my share of the tips, so that I had enough to eat and somewhere to live.(not every business has accomodation available).
As a manager, I soon learnt that the staff who made the most gratuities, both restaurant and bar, were just as good as an advert in the Worthing Herald, or any other media.
To the day I die, I will continue to tip GOOD service, and return for more.
Haley Road, Lancing