I delivered pizzas for about five years, from age 26 to 31, in the wake of my bad divorce. It was great for a while, but as I got older, out of debt, better off financially, and started valuing my free time more, I started phasing the job out.
Having a string of increasingly bad management, and a road-rage incident the culiminated in near head-on-collision also played a role in phasing it out!
In my case though, I had a full-time job, and the pizza delivery was on top of that, so that's where the lack of free time came into it.
You can actually make some pretty good money if you start picking up some closing shifts, especially Friday and Saturday night. I used to average about $15-16 take-home (tips plus the weekly paycheck). However, I didn't have insurance or 401k to deal with, as I got that through my main job.
On the down-side, I'd often put 200+ miles per night on the car. And the cars did break down a lot more often, and needed more maintenance. And I did have one car get totaled, when I got t-boned in the parking lot by a girl who ran a stop sign.
Admittedly, there was something satisfying about that job. The harder you worked, the more effort you put into it, the more money you made right then and there. So you could see the results of your hard work. If you were lazy and slacked off, you didn't get as many deliveries out, you didn't get the best shifts, etc. In contrast, at my office job, you could work your butt off and, if you were lucky, get a 3-5% raise. Be mediocre about it, you still might get 2-3%. Slack off and you might still get 1-2%, and job security was right up there with the Pope!
I don't know that I would depend on pizza delivery though, as my only job for the long-term. It can be hard, thankless work that gets tiring as you get older. Plus, it can be downright dangerous!
What about a job waiting tables, or bartending? It would still bring in a lot of cash money, but without the added automotive risks.
