I had to pay a departure tax to go to Chetumal a few weeks ago. I can't remember how much. Maybe 10bz each for the 2 of us. Then a week later I had to pay a departure tax plus a port fee?? to leave Chetumal. The departure tax I knew was coming and that was paid at a bank.
That is not counting $28 pesos (a little over $2 USD)cargo fee I paid to the port authority for a large but light object I brought back. I asked twice if the cargo was on board and they said yes. Finally when boarding I stopped and blocked traffic entering the ferry and asked again because I knew it wasn't on board as it was nowhere in sight and was too large to put in a hole below. They had to send someone up to the head of the pier to get it before we left. I agreed to hold on to it in the aisle below and all turned out good.
Governments need your money.