+1.

Fitting a bike on a showroom floor will only get you in the ball-park imo. And short rides around the LBS parking lot and/or minor time spent on some sort of stationary stand will not take the place of real saddle time that accurately reflects the actual type and style of riding that you do.

Any competent rider (as stapfam and others suggest) should be willing and able to perform the necessary fitting/adjustments required by all but the most serious bicyclists and/or pros.

I'll also add my opinion that spending serious money on a "showroom floor/parking lot fitting" would often be better spent on buying a higher grade bike in the first place.