Dog meant to drink from toilet

At the meet and greet the owner mentioned the dog drinks out of the toilet. I assumed this was something she was trying to avoid for obvious reasons but when I arrived for the sit there was no water bowl for the dog. She also asked me to not clean the toilet with any products because the dog would drink them. I find this to be really unhygienic. He's a giant breed dog who drools absolutely everywhere - like it pours out of his mouth especially after drinking, and rubs his head on the furniture/people. Seems unhygienic for both dog and human. I put water out for him but he's not stoked and begs for the toilet. Interested in people's thoughts!

He does drink from the bowl but I don't think it's as much as he'd drink otherwise - he craves the toilet.