Here I explain the situation in English, because Tripadvisor.com is a worldwide website, so that more people can read and understand. The issue in this case is not the language problem neither the price problem, it is about the respect to the other party's rights and the limit of taking advantage of the other party's generosity.
The fact is: when the clients came to our motel, it was around 10 o"clock on the Saturday morning. The regular check-in tome is 3 o'clock afternoon in our hotel. For the clients' convenience, we gave them an early check -in and off ered all the free services included in the room price such as parking, wifi and informed also the breakfast time and place.At that time, they didn't ask anything about the battery charge for their electricity and gas hybrid car until almost 2 hours later we found they were charging their car with plugging in the electricity outlet on the hotel side wall. We unplugged the cable and wrote a paper notice to ask them to contact the reception about the charging.
Afternoon the clients back and we explained that it was not correct for using our property without our permission we would require extra fee for their charging . When we told them the charge is 10$ per hour in Montreal electricity car charging station as we studied on internet, they started showing their unhappiness and arguing that there is no this kind of charge in other hotels and threatened that they would write a negative review.
From our hotel side, the comment is not a fair opinion. Each hotel has different policy. Some hotels charge for wifi, the other hotels charge for parking. Our hotel offers free wifi, free parking and free continental breakfast. Besides, the other services may be subject to the surcharge or not offered to the public at all. the hotel has the right to make the price decision. From the other words, it is equal to the clients that they have the right to choose the service or not, if they think the price of the service is too expensive.
But for one point ,it is undoubtedly clear,using the other party's property without owner's consent is not a kind of appropriate behaviour.