I think it would be at least as good as a break even proposition since the deadbeats who don't tip would have to as part of the meal price which should create more cash flow to pay for the added cost of a higher wage
Back when I was a waiter, it was actually a very, very small percentage of patrons who didn't tip or were stingy with the tip. And this was at Denny's, in a not-so-great neighborhood, where we had a lot of senior citizens on a fixed income. Then there were families with kids, who were strapped for cash. And then there were, well, poor people! But even here, I'd say it still averaged out to around 15%. I would've done much better though, if I had worked at a more upscale restaurant, but truthfully, back then there wasn't a whole lot around here. This was before places like Applebees, Olive Garden, Outback Steakhouse, etc had really sprouted up. I guess I could've tried the Jasper's next door.
When I delivered pizzas, it was also a very small portion of the customers who were cheap/non-existent with the tip. Delivering pizzas was also kinda funny, too, because we really didn't strive for 15% there. I'd say that I averaged a bit over $2.00 per delivery. Logically, with pizza delivery, the tip should depend more on how far the customer is from the store, and less on the actual bill amount. The further out you are, the more you're benefitting from the driver's resources (his car and fuel) and time (it would take you longer to drive to the store), and also, the driver is literally putting his life on the line for you (driving is statistically one of the most dangerous things you can do). Plus, if you're further away, the driver could be making more money with more lucrative closer deliveries, and could probably deliver 2-3 orders in the time it takes to deliver yours.
Often the tip depended on the price point. If an order came out to $15.74 ($14.99 + 5% tax), we'd usually get $2.26 for a tip, but occasionally we'd get $3.26 or $4.26, and once in a blue moon, $1.26. If it came out to $16.79, most often the tip would come out to $3.21. Although sometimes it would be $2.21. Rarely would it be $1.21 though. But now, at $18.89, it was pretty often that we'd just get a $20 and "keep the change". Although a $2.11 or $3.11 tip were still fairly common. I quit delivering right about the time that we started accepting credit cards, so I wonder if that's had much of an effect on the tip?
Oddly though, some of the most generous tippers were right around the corner, while the cheapest ones tended to be on the fringes. Overall though, I'd say maybe 5% of the customers, at best, were cheap/annoying. So the vast majority were really cool.
So in getting away with the tipping system, I don't really think that you'd stick it to that many deadbeats, although I agree it would be nice to get them to pony up their fare share. One thing I'd do, when I used to deliver, was that if I KNEW I was going to a deadbeat's house, and had other deliveries in the car, I'd take the others first, regardless of what order they were originally placed, if I knew I could still get them all there in time. Unless doing so was out of my way. I'd always try to plan my route to do the shortest amount of driving, while still getting them all there on time.