It says ladies only but thought since this thread was bumped and other hobbyist are on it. I might as well chime in...
From a hobbyist perspective if I plan on a meeting that may cause a transaction of 300or more, large bills are easier to carry without drawing unnecessary attention to my wallet while standing in the cafeteria line at lunch. Under 300 is a mixed assortment (there could be a large one or two in there) and I try to avoid singles and coins out of respect for the individual I'm meeting. Hoping the respect will be reciprocated and she won't go BSC on me.
Large bills for small transactions draws negative attention which you don't want or need. The opposite is also true.