I've made the "call of shame" several times:

• Had my 2nd flat of the ride and had already used my spare tube.
• Had a flat and realized that when I moved my panniers from my winter bike to my regular commuter that I hadn't also swapped the spare 26" schrader-valve mountain bike tube with the 700c presta-valve road bike tube.
• Had a flat and discovered my frame pump had broken and wouldn't pump up the tire.
• Snapped a chain 5 miles from home in sub-zero weather. Walked 2 miles until I found a phone I could use and then called my wife for rescue for the remainder of the trip. I did sit in the bed of the truck with the bike out of principle.

Several other times I've had issues but have been within a couple miles of home so I just walked the remainder of the way and pushed the bike.