If you're making your own meals ($3/meal), yes, it is expensive. If you eat out then it is much more reasonable. A single eat-out costs ballpark around $6/meal, so assuming you did that twice it would break even.
I agree re. sample size. $85 in one go is hard to justify to the +1 when all you're really buying is food. $6 here or there is easy to ignore, but $85 is a weekly grocery shop in everyone's mind.
I wonder if price will come down as they expand? It might be wishful thinking to be honest, but I do suspect there are a fair few people who would happily try it if it was closer to $4/meal rather than $6/meal per now (i.e. $8/day from $12/day).
PS - I have to admit my three reasons for not trying it is: price, manufacturing problems/delays, and also I remain unconvinced that we know enough about nutrition to create this product that won't caused health defects in the medium to long term.