I have owned one restaurant, my roommate has owned three, and his partner a few more, and I consider myself pretty wired into the local restaurant scene. It is my experience that a landlord will almost always demand a personal guarantee.
Landlords are not stupid. If a lease is shielded, as it were, from the owner's assets by a corporate structure, the landlord has little ability to enforce lease provisions should an owner chose to walk away from his business. Granted, the landlord could put a lien on remaining restaurant assets, but in reality those tend to be minimal, and the landlord would probably be down a ways on the claim list, with local government (unpaid sales tax, etc.) at the top.
That being said, everything is negotiable, and a landlord desperate for a tenant in the post-2008 economic environment might be amenable to discussion of the issue. It helps to be highly capitalized, or have a solid track record with other restaurants or businesses. The landlord has to be super-confident that your business will be around for the entire term of the lease. If you are a thinly capitalized newbie, the landlord may be willing to take a risk on you, but he will want that personal guarantee.