Yes, I knew of two up sell strategies:
1. A couple of friends attended a $795 3 day option trading classes in San Diego. Taught some options basics but most of the time they were selling their services to manage your money for you calling it mentorship. My friends could monitor the trade real time and witnessed how the pros selected what and when to trade. They charged a fee and 20% of the profits but won't share the losses, i.e., like a hedge fund. One guy gave them $100K to trade. Six months later that $100K became $40K and he terminated the relationship and learned a painful lesson.
2. A couple of friends attended a free half day trading seminar in Southern Cal that supposed to teach a patented supply and demand strategy. All the instructor did was trying to sell them a $399 class on what is supply and demand and how to apply that strategy. One guy took the $399 class (which was discounted to $199 when he signed up immediately). Most of what they did in the $399 class was selling a $2,999 class. They have a $30K class which I assumed is when they really teach you their method.
FTC just busted these guys. I honestly imagined this kind of garbage disappeared back in the early 2000's.