"Diseases of the rich" has always seemed like a useful metaphor for one way to decide on what product you are going to build. Does it heal a "disease" of the "rich"?
His comments between songs are at least as funny as the songs themselves. For many years I thought that recordings only existed of those comments for An Evening Wasted and That Was The Year That Was. Then I discovered The Remains of Tom Lehrer, a 3 CD set that includes, not only the original Songs By Tom Lehrer (straight off the 10 inch LP), but also a live recording of the same songs from a concert, with comments between the songs! (This set also has studio recordings of the songs from An Evening Wasted, done before the live concert recording.)
Just to give a taste, before he even plays the first song in the concert version of Songs By Tom Lehrer, he gives a biographical introduction of himself, as though he were a toastmaster or an impresario. Here's how it starts (at least as much as I can capture it with just typing):
"Endowed by nature with perhaps the most glorious baritone voice ever to be heard on an American stage since the memorable concert debut in 1835 of Millard Fillmore; endowed also with twelve incredibly agile fingers..."
An example: Angry Birds 2 made hundreds of millions by selling at 79p to hundreds of millions of people. Think what it takes to make an app to sell to 10 rich people to make the same amount of money.
I'm not saying it's impossible to make money selling to rich people. It's just in no way the only way. Many ways of making money involve selling to many people.