One has to wonder how Hayate's parents managed to support themselves before he was born, since "Mother" is not just a gambling addict, but a bad one and always loses, and "Father" absolutely refuses to get a job. Even though they've been shown to scam people with fraudulent art pieces, Hyate is still the one who did the lion's share of the work in that regard. Even stealing lunch money from kindergartners is nowhere near sufficient income to do anything.
Hayate's pre-butler life as a whole. Think about it, he's pretty much been neglected by his ne'er-do-well parents as early as when he was born, and has been forced to work to pay off debts at the tender age of six (and whatever money he made gets instantly sapped away by his parents), thus having to skip studies and even school. Had it not been for his Charles Atlas Superpower and Determinator status, he would have either a) died from work-related stress or other ailments due to his lack of immunization treatments, b) come out an Empty Shell, or c) committed suicide due to how horrid his life is (which he actually contemplated doing after his father stole his money he earned until Athena snapped him out of it).
How long was Athena alone in the Royal Garden? It appears that one month inside the Royal Garden is equal to one day in the outside world, but it's not clear how aging works inside the Royal Garden.
In chapter 491, Ruka tells Nagi that if Hayate pays off his debt and quit being her butler, then he will devolve into a NEET and eventually get killed. Whilst that would normally seem like just a joke and little else, the fact that he suffers from "poor man's syndrome" means it could very well be a possibility.