I'm surprised it hasn't actually come to that. What you will probably see in the not too distant future are robots doing these pizza deliveries. Armed, bullet-resistant robots.
The MRAP might be overkill, but I'll bet a used Brinks-style armored truck would work. Plenty of room for pizza and 12v warming ovens on the inside, plus advertising space on the outside. It could play music through loudspeakers, like the old ice cream trucks.
Of course, if they used that rig only in bad neighborhoods, it'd somehow be discriminatory.
You do realize you’re talking about people who rip copper out of huge AC units and even railings from churches. I’m sure anything robotic would be quickly grabbed and sold for scrap. The armored car idea is the best-but if you have to go to that extreme you might as well use an armed tank. WHY service an area that dangerous at all? Why is selling $5 worth of dough and sauce worth endangering a life?