Even if you dont ask for it! One time I just got done ordering my sandwich, they grab the mayo bottle and say "you want mayo?" Then jizz out half the bottle all over it before I can say no.
As an ex sandwich artist, now sandwich artiste (I quit and do it at home for myself now):
I STARTED putting normal amounts of mayo. My owner was 1st Gen Chinese and frugal as fuck so she drove that into us "1 line, half if they ask for light, 2 line if say more" were her exact words
Sooooooooooo many people said "more. No, more" that we all started defaulting to more when someone asked