Wikipedia:
http://en.wikipedia.org/wiki/Abundance_mentality
Likely you will find, like me, that if you 'show others the path' where they can learn lots about Excel (or about healthy diets or lifestyles, or being better people / personalities / partners, or having wealth, or just about anything else) less than 5% of people will follow that path.
There are many, many opportunities for using Excel and even if there were 10 times as many people with skill levels 10 times what they have now there would be plenty of opportunities still.
So, don't be secretive with your knowledge, please. You will grow and be more appreciated and better by sharing the knowledge with as many people as you can. Look at this forum as an Excel-ample. Bill Jelen and hundreds of thousands of people are improved by this forum! Wow, eh!
And the same with all the other great Excel web sites that are often linked to from threads - Debra Dagliesh, Chip Pearson, Charles Williams, Jon Peltier, Rob Bovey, XL Dennis, etc, etc, etc.