Why is tipping 15% the standard? TO MAKE THE JOB/RESTAURANT VIABLE....
Not all the servers work all day everyday. MANY are only there for the busy hours because it wouldn't make sense, nor would it be profitable for the business to keep all their servers there throughout the entire day. I worked at one very busy restaurant where the rush would require approx. 14 people, but the down times you could get by on 4 or less. Having all 14 people working all day wouldn't make sense, nor would it be a sustainable business model. I'm pretty sure any of you can agree with that.
That means a lot of servers are only there for the rush, 3-4 hours max. Not everyone makes $200 tables/ hour. Lets assume someone makes $100table/hour, over a short 3 hour shift. + their $8.90 (- income tax and deductions, probably around 8) and 3.5% house take that we've been using. so @ 15% tip that server made $24 wage + $45 tip - $10.50 = $58.50 for an entire shift. @10% tip you just subtract $15, meaning they only make $43.50. 43.5/58.5 = ~74% So while it may only be 5% to you, its a ~25decreas/33increase% difference in income for the server.
Is it really worth while to come in for a shift or keep a job that pays 43.50 a few times a week? Probably not. You need to consider that you have to take out time required to travel to and from work, parking maybe, the cost of travel.
Should restaurant owners incorporate this cost into the cost of the food? Lets say the industry decides to go that way and that the standard 'tip/increase in wage' as a % of the bill becomes 12.5%. That means the cost of the dish would go up by approx 25% for you to cover the costs of the taxes deducted from the server, + the increase contributions required of the restaurant. That also mean the customer is out another 10-15% over what they were paying. People will most likely eat out much less as a result, the restaurant will suffer, and servers will lose their jobs. It's a lose/lose/lose situation for everyone in that scenario.