TICKET PLEASE - VERY FUNNY TRANSPORT JOKE

Three lawyers and three engineers were traveling by train to a conference.
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At the station, each lawyer bought a ticket whereas the engineers bought only one ticket between them. "How are you going to travel on a single ticket?" Asked a lawyer.
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"Wait and watch," answered one of the engineers. When they boarded the train, the lawyers took their seats, but the three engineers crammed into a toilet and closed the door behind them.
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Shortly after the train started, the ticket collector arrived.
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He knocked on the toilet door and asked, "Ticket please." The door opened just a crack and a single arm emerged with a ticket in hand. The ticket collector took it and moved on.
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Seeing this, the lawyers decided to the same thing on the return trip.
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So when they got to the station, they bought only one ticket. To their astonishment, the engineers didn't buy any.
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"How are you going to travel without a ticket?" asked one of the perplexed lawyers.
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"Wait and watch," answered an engineer.
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In the train, the three engineers crammed into a toilet and the three lawyers into another nearby.
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Soon after the train started, one of the engineers got out of the toilet and walked to one where the lawyers were hiding.
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He knocked on the door and said, "Ticket please."