People love cash, if it is easy enough to use, there are only 6 people between you and everyone else.
A propos: https://research.facebook.com/blog/three-and-a-half-degrees-of-separation/
...makes me want to cry about my Erdös number.
Too bad I'm not in the subset of people with a lower Erdös number than their facebook average degrees of separation, close call.
The former will be probably harder to decrease than the latter.
Surprisingly low numbers computed there, we live an interesting time.