This may be the case with your neighbor, especially since it appears you've been monitoring the supposed activity the neighbor claims and seen nothing that confirms this.Some home owners are just nosy people who would rather see an empty building than tenants living there.My story....we once had an incident where a young man decided to ride his bicycle down to the local Kroger very early one morning to buy his uncle some soda. 

This article & video tells the story of why Philadelphia has the highest bicycle commuter rate of any city in US of 1million+http://www.treehugger.com/bikes/enigma-philadelphia-bike-success-story-despite-having-little-infrastructure-video.html

Heck, my primary source of transportation is my bicycle which has served me well in saving me a nice chunk of money and giving me a workout.However sometimes even the best laid plans can crumble.

Mentally debate do you need this shirt, shoes, bicycle, new iPhone 13 max +, etc.?

Any nearby races—triathalon, bicycle, etc.

My partner in the sporting goods and bicycle industry said we should go into real estate.

He had a little tiny folding bicycle in the back of the plane, and at least a few of the houses were within biking distance of the airport.

Here's a story that I find analogous to this situation.When I was 16, I rode my bicycle(with a group of 12 others) from the West Coast to the East Coast.

He had a job at a local hotel (doing maintenance) and rode a bicycle 7 days a week back and forth to the job; this was a distance of at least 8 miles one way.  

Some of those islands outlaw motorized vehicles, the only way around is by walking, running, bicycle or horse.