When you travel without panniers, you are less dependent and more likely to use restaurant and pay for accommodation. Obviously it will not be a problem in Italy. Unless you will be travelling in the Alps in very remote areas, you'll be able to find accommodations and restaurants everywhere. You can still use a saddle bag, a frame bag, and handlebar bag allowing you to carry a lot of gear, possibly even a tent and a sleeping bag depending what season you will be travelling. Ortlieb came up recently with a bunch of bags for bike packing gear allowing lightweight touring without panniers. The Seat-Pack has very good reviews on the Internet: Ortlieb Seat-Pack
. Italy is also a good place to spend time with locals. You can ask to pitch your tent in their backyard, and you'll often end-up invited to stay in their home. Great to learn about their culture. Be prepared to be singing after a few drinks!