I've done a 'boys' barge holiday, I'm pretty sure you're not supposed to get properly bat faced but we did get more than a little squiffy at times (as you can imagine) and we did batter into a moored boat which fortunately was empty at the time. We checked for damage and vamoosed sharpish. There is a canal etiquette as well, and I'm pretty sure we were reported for being ball bagged although with hindsight it may have been an empty threat. The barges can only do about 4 miles an hour so you should have plenty time to avoid each other in theory, although......