Hofstra has historically been generous with need- and merit-based aid, which they combine into one package (at most other schools, they are separate processes). So when you apply for financial aid, the financial aid office uses a formula that incorporates both need and merit to generate a scholarship for you. According to the presentation they gave admitted students this year, most people get about a half-tuition scholarship. I can't speak to how many get full tuition, but presumably some do.
I wouldn't expect this from most mid/low-tier schools, though. Hofstra is a relatively new school and they seem to have set aside funds when the school opened to allow for this generosity so that they could compete with established schools in building a high-caliber class.
The other thing you should know about merit aid is that since it's usually awarded by the admissions office instead of the financial aid office, there can be some flexibility. It might be more accurate to call it "recruitment aid" than "merit aid." For example, if you are a desirable applicant and you get grants or scholarships from one school (need- or merit-based), you can tactfully go to another school that's accepted you and ask them to match it. This can be a way to get funds when for whatever reason one school's formulae don't benefit you but another's does. I would guess that well-endowed private schools tend to have more of this discretionary recruitment money than public schools.
