When I backpacked Italy just after graduating from University, I had an extremely limited budget. Every cent counted. So, when I saw how much hostels cost in Venice, we decided to opt for the cheapest option we knew of: camping.
Now, camping in Italy is not camping in America. Imagine our surprise when we arrived at our campsite and found that it was actually a sort of mobile home, equipped with beds, bedding and an en-suite bathroom with a clean toilet, and hot shower. Wha?? Awesome. The camping area also had a swimming pool and a cafe/restaurant. The place was at least half the price of the other accommodations in Venice.
The only downside is that the hostel is about 20 minutes by public transport out of the city central. Seeing as none of us spoke Italian, we were worried about how we were supposed to find the place (even though we had directions). But, once we got on the bus, we just followed the other foreign faces and it was no sweat.
The same thing happened on our way to the Florence campsite. In Florence, the place was located on a hill above the city. We had a bird's eye view from the cafe. This particular campsite was only 10 minutes outside of town, but the room itself was more like a glorified tent. But, everything was clean and nice.
At both campsites, we met some pretty awesome people and had a really nice time. In particular, at the Venice campsite we met three girls who I'm still Facebook friends with today. I highly recommend either place. There are likely some not-so-great camping establishments as well, so I would still do a bit of research as with any place I plan to stay.
Bottom line: Camping in Italy is > Camping in America.