Well, I own a Sony MDR-7506 and I AM NOT ASHAMED OF IT.
This headphone is ONLY sold in the professional line and is intended for monitoring (not mixing).
It was never meant to be used as a hifi headphone. They have a very different and huge line for music enjoyment and the MDR7506 is not part of that line-up.
The reason you see these used in studios is because they are designed for this usage and work well for that usage.
Just like one sees some other headphones in studios too for certain applications.
The fact that some believe that something that is used in a studio is thus also good for music enjoyment is an incorrect way of thinking. In studios it is used with a specific goal. That is not the same goal as the end product (consumable music).
The fact that some prefer the tonal properties of the MDR7506 over other headphones is just that. Preference.
Nothing to be ashamed off. Most people prefer some extra treble as it gives the impression of 'more detail' and is exactly why it is used in studios.
It can ruthlessly show sibilance and sharpness and can highlight 'details' during monitoring.
Studio headphones are designed for studio usage. Some can be used for music enjoyment, with or without some EQ.