Thanks for the link - will read. I thought it interesting the McElreath’s model treats the mixing parameter pi as continuous (he uses a Normal with invlogit link), presumably to keep parameter space smooth and let his MvN priors work…
EDIT:
Also someone on that thread called such a mixture “zero-augmented” to indicate of course that the continuous distance of choice might not have any support on zero. I quite like that terminology, will use.