Quoted from docquest:Part of it might have to due with rights issues if the game has music or voices.
Another part might be thats what a majority of people expect pinballs to sound like.
Also in many instances where pinball is in a scene it's just for background ambiance. If it had music or voice callouts being played it might distract from the main action more than simple bells and chimes would.
Even though the sound is wrong, I'm just glad pinball still shows up in mainstream media every now and then.
Or it's a lazy Foley artist