What is a single supplement and why do you make solo travelers pay it?
The value of the single supplement:
The single supplement is the cost of the other half of the hotel room for a traveler staying in a room by himself or herself. It is the price of half of the hotel room multiplied by the number of nights. When two travelers share a room, they split the cost of the room in half. When a traveler stays alone in a room, he/she is charged for the entire room each night. This would be the case if one booked a hotel on one’s own (think of the difference in price if you split a sandwich or have the whole one to yourself. Or perhaps a better comparison: if two friends went to NYC together and were deciding whether to share a room or have their own rooms).
To calculate the per person tour cost, we divide the hotel room price in two and the entire tour cost is based on per person, double occupancy. (The method of pricing tours this way is an industry standard and we follow it so as not to confuse things.) The benefit of having a room to oneself is reflected in the single supplement.
The single supplement reflects only the total of the second occupancy fee of the hotel room for all nights of the tour - an expense passed along directly from the hotel - and not any other aspects of the tour. In other words, travelers staying in their own room will pay the same portion for all other tour costs, such as meals, transportation, admissions, etc., as travelers who share a room.
Many people prefer to have the privacy of the room to themselves. Others prefer to avoid the single supplement fee and can do this by sharing a room.