If you have grass, instead of going dormant in winter it'll kill it as if you'd laid plastic sheeting over the lawn. The lawn needs to breathe and a heavy layer of leaves will suffocate it.
I am not big on raking, but there are three teenage boys in our neighborhood. All three want on the order of $40 USD to mow our yard, and it's not even that big a yard. It comes out to about $30 and hour if I would hire them. I don't make that much so I am not playing them.
Neighbors that refuse to rake can be worse than those that refuse to mow. It sucks to spend the time raking your yard, only to have your neighbor's leaves blow onto your property over-and-over.
I use a mulching mower now, after years of raking my neighbor's leaves. I actually don't even have a tree on my property, but if I let it go, leaves from the surrounding lot's trees will cover every inch of my lawn.
But I have since come to better ideas. Mulch them with the mower.
If your blades are sharp, theyll be dust and will enhance the health of the lawn. Now I give my lawn a good mow at the end of the season and mulch up the leaves.