That justification is more acceptable, but still a poor excuse (which doesn't sound like your fault), and if anything highlights the problem with the focus of user-centered design.
I'm sure you'd agree, design isn't a democracy. Clearly, your users are wrong.
Mobile sites suck; I detest when I get redirected to them on my Android phone. About the only time they are justified is when the site is heavily dependent on mouse hovering and other desktop-centric interaction idioms.
I'm sure you'd agree, design isn't a democracy. Clearly, your users are wrong.