Just guess here, but two factors come into play.
One, the ground noise theory.
Mornings are the quietest part of the day, no other people making noise, no TV’s on, no trucks going by, and no matter how quiet you try to be it seems like you make more noise in the am. Something so much louder then this environment would seem hideously loud.
Two, the car theory.
Ever get out of your car after listening to a great song and singing along while you drive, then you stop to get your eyes waxed or a Brazilian bikini line, and when you return, you turn the car on and the radio is blasting and you’re thinking…what was I friggin deaf?...the nice part is this theory also uses the ground floor noise theory, its not the level alone, but the level compared to the available sound around it.