I took the post to be a reasonable question...no assumption about SAHM's (why would you assume that?). There are many people out there (such as myself) who already have plans too that save money on cell-phone bills....yet they change their numbers at the drop of a hat, whether a SAHM or a person who works outside the home.
I don't understand your anger or offense with this post.
One person can often change their number and the other doesn't have to, without affecting the plan.
Perhaps her H is cutting OW off, I sure hope so...that'd be a nice thing All that was being pointed out is that, it may not necessarily be the case....to keep her grounded. Sometimes when we believe something because we so badly want to we become blind to reality....that's all.