you mean they wont allow you them because u have a healthy weight bmi??!
Dont mean to sound harsh but if that is the case then technically you are at a healthy weight and henceforth dont need total food replacement!
However I know how it can feel if you do want to lose a few pounds and are unhappy with your current weight.
But I suppose if they gave total food replacement to everyone with a healthy bmi they would have people suffering with serious eating disorders i.e. anorexia abusing the product, or people using it for a quick fix that dont clearly need it.
My mums on maitenance products as she has a healthy bmi and felt like she needed to lose a few pounds, but she has lost some weight.
all the best x