Yup- there is inequity in pay sometimes. You just cited an example.So, if you go to a pizza restaurant and they come to your table to take your order and then bring your drinks and food order and then refill your drinks one time, the server has made 3 tips to your table. The same holds true if you're eating at a steak restaurant but the bill (for the same number of people) is a lot more at the steak restaurant because the food is more expensive. Why, then, should the tip be based on a percentage of the bill? The server at either restaurant is doing (more or less) the same amount of work but normally gets a higher tip just because the food costs more which had absolutely nothing to do with the service rendered by the wait staff. For example, 20% of a bill of $50 for a party of 4 to eat at a pizza restaurant would be $10 but a bill for a party of 4 at a steak restaurant might come to $150 and so the 20% tip would be $30. The wait staff at each restaurant would be doing ostensibly the same amount of work so why the tip disparity? Just sayin'
I would guess the steakhouse jobs are in higher demand than the pizza jobs too.
It happens in a lot of industries.
Staying in food service- One fast food joint may pay $11/hour starting wage while another right down the road or even next door pays $8/hour starting wage.
Grocery chains are another place where pay can be significantly different depending on company, yet the job of cashier is pretty damn similar.
Teachers are another example- from state to state, the pay differs. District to district it can differ. Even elementary to high school can differ within the district. All the teachers are teaching and it could be argued that elementary teachers 'work' more in many situations.