The people asking probably don't think they have no clue of the costs of what they are asking for, they think they have a vague idea of the relative costs based on their perception of what is involved and their past experience of other changes.

Now, these ideas may often be very wrong, and may be in fact so wrong that "no clue" is the best description, but its not, for the most part, dishonesty when people act like they have some general expectation of the cost.