Why get an expensive tuner?Am I missing something?

You have already convinced yourself and concluded it can't possibly ever sound good, when it appears that you actually have never heard an excellent tuner properly setup. So our words may not mean much. I suggest you go out and listen; and discover for yourself.

I recently gave a decent mid-fi tuner to a professional musician friend who always used his old worn out 1970s receiver as a tuner through the tape-out, because he assumed like you did. He is now shocked at what he has been missing all these years. He hardly listened to the radio before. Now he has it on all the time, when a CD or LP is not playing.

It depends on the radio stations you listen to. A good NPR or college station (read: non-compressed signal) can sound as good as, or better than CDP or turntable. So the answer to your question is yes a good tuner really makes a difference.
Cheers:~)

>as good as, or better than CDP or turntable

Waitaminute. How can it sound better than, unless perhaps your CDP or turntable are really poor?

I can say that until I got a Day Sequerra I was content to use the tuner for background music. Once I heard what a great tuner could do, I got a top notch outdoor antenna with a rotor and have been listening a lot more seriously since. A great tuner can certainly help you in finding sonically good CDs (even taking into account the dynamic compression on the big orchestral stuff, you can hear the sonic merits of a recording), and when you get the occasional live broadcast (on WQXR here in NY, you get the Met Opera broadcasts, NY Philharmonic and, best of all, small ensembles in QXR's studios) it is really something special and can outperform a recording (Drubin, that's where in my view it can outperform a CDP or TT; or, of course, if the station uses a Burmester or similar CDP and a Rockport TT, then maybe it can outperform a listener's system, but that's not really likely, and I do feel that the dynamic compression the stations use can limit the material that would sound better). Plus you get a lot of great music, of all types, for free!