Bad fuel pump after oil change?

Today, I took my 2005 Jeep Liberty Limited 6 cylinder in for an oil change and tire rotation at a local Pep Boys. They also did an AC check as it was blowing warm. After picking up the vehicle and driving it for a moment, the car was shaking when I got to a nearby stop light (about 30 seconds away), and it then shut off and would not restart. A group of military guys were kind enough to help push it back to the shop.
Pep Boys looked it over and determined there was very little fuel pressure and advised they could fix it in a few hours for about $1100. Needless to say, I had it towed back home for free thanks to my insurance. This brings my ultimate questions.
1. Will a fuel pump just go bad suddenly, with no warning? The Jeep ran perfectly with no starting issues at all.
2. Is it possible in the maintenance I described to cause this issue?
I have checked thrice over all the hoses and show nothing loose. Oil level is fine. Any help and advice is appreciated