I have the opposite problem at my dealer. Our online credit app caps income at $999,999 per year where it is not an everyday problem but every now and then I have to tell people making more than that to “lie” on the credit app.
But more to the point, is most likely the F&I manager who will inflate the income since they can see the applicant’s credit history and what will get them approved by a bank. There are a few people who lie on the credit apps by either making up income or including spouses, parents, etc. But as electic said, it is up to the lender to verify the information provided and red flags are typically raised in these situations. For example, I see deals go into manual review if the customer’s car payments changed from $200/mo to $1000/mo or if they never had a payment before. So I have a feeling there is more to this story than someone submitting an app with an inflated income since someone making $660/mo will have a very limited credit history or high revolving credit.