I see no cheapening of any design re this lounge - it is a rather luxurious area and there are many images and descriptions on-line
The showers and area are firmly controlled by the experienced staff and users shown where to go and which shower room to use.
The control of the facility is necessarily fairly tight as it is very normal to need to make a booking.
There would be no stray passengers wondering around the area without staff being aware and so any 'frantic knocking' would indeed seem to be odd