Salsachica,
I've used a shared bath several times over the 15 years I've traveled to Europe. It has never, and I repeat never, been a big deal. Americans (we are a picky breed) have this big phobia of a shared bath and seem to almost always opt for the ensuite making the "bath down the hall" virtually unused. The ones I have used were spotlessly kept, about 2-3 doors down from my room, and far more spacious than many of my ensuite baths. Sheesh...you've already shared a bath in a college dorm and hostels (with much less privacy I might add), you use "public" toilets every day at work or school or out shopping, you share a bath with family members every day, what's the big deal? Oh yeah....are robes and slippers provided? HAH! At a property with the bath down the hall?!! Bring your own, and don't forget the shampoo and soap, too. Towels will definitely be left for you in your room, though (especially in Italy) don't expect plush, fluffy terrycloth...most of Italy's bath towels are glorified tablecloths--large, but thin. You probably won't be given a facecloth, either, so if you need that, be sure to bring one of your own or the neat disposable ones from Dove or Olay or similar. I bring disposable face cleaning cloths and one of those bath puffs for my shower gel...I can throw the face cloths away immediately and the bath puff away at the end of my trip and have slightly less stuff in my toiletry kit to take home. This ain't the Hilton, baby (and why would you want it to be??). And one more thing....a "shared bath" is down the hall, and "ensuite bath" is in your room, but if you come across a "private bath" it could be in OR out of your room, but is for your exclusive use only. I always clarify if a property offers me a "private" bath.