Numbers may be rare in literal texts, but writing down phone numbers were one of the main reasons why I decided to learn FitalyStamp. I had a mobile phone with a messagebox for my profession then, and since people wanted to save their money they would speak a very fast "My name is XYZ, please call me back on 0123456789".
When I tried to write the number down with graffiti it would take four or five repetitions until I managed to write the number down correctly - and each repetition with the mobile would cost about 50 Cents!
With FitalyStamp and "direct letters" I can write the name and the numbers at once in the most cases. So it saved me a lot of money.