I get lots of "invitations" to conferences, business breakfasts, and seminars. There all very friendly. But then when I open up an attachment it says Conference = $2,500; Business breakfasts = $125; Seminar = $400.
Invitations aren't always what they seem. A bit like fully-funded, non-dilutory, no up-front costs; which turn out to need 20% down payments before you see a cent.