There may be a tax-savings angle to that. Some states, like Nevada and Massachusetts, charge vehicle property tax based on the year of the car and buying a car "one year ahead" can result in a reduced rate for that year compared to same-year tax rate. That might short-term make leasing cheaper. I only noticed it in passing when I leased a vehicle there.

Additionally, magazines are typically published with the date they should be removed from the newsstand, not the date they should be sold. This is different from newspapers which typically publish with the date they are first available.

Side-Note: this is why the current issue of Time, which is a magazine, will have a cover date a few days in the future while The Economist, which considers itself a weekly newspaper not a magazine, will have a cover date of the previous Tuesday.