I personally like the idea. I will go along with Topher and the cotton, this is an OSHA requirement for some aspects of electrical work and regardless synthetic is dangerous in more than just fire, it also seems to prohibit evaporation of perspiration for cooling the body.
We have a few large accounts (hospitals and manufacturers) that prohibit any writing, logo's, or symbols on any clothing with the exception of company logos.
This helps some of the "not so bright", "arrogant", or "striving to be rude" employees know how to dress for work and actually for society in general.
If anyone is using Internet Explorer go here, http://www.iespell.com/download.php
for a nice spell checker.