Unruly behavior can cause a passenger to be removed from a flight. Two Air Canada flyers, however, were escorted off their Las Vegas to Montreal flight on 26 August for complaining about a dirty, smelly seat.

A co-passenger sympathized with the "maltreated" passengers and posted about the incident on social media on 29 August.

According to the whistleblower, Susan Benson, a nearby seat was soiled with vomit and the airline crew apparently failed to clean it up properly. When the passengers sat down, one of them called the flight attendant to complain that the seat and seatbelt were wet.

The flight attendant apologized and told them there were no other seats available to transfer to as the flight was full. The passengers then asked for the supervisor, who also apologized and said they had to sit in the wet seats.

As a compromise, the passengers asked for and were given blankets to cover the seats. When they were settled, the pilot approached the two and told them to leave or he would call security. They refused and security staff escorted them off the plane.

The airline later reached out and apologized to the ejected passengers but, meanwhile, health authorities are investigating the incident. Aside from motion sickness, bad odor may cause a person to vomit.

Pornpreeya Keng, 27, was traveling on a low-cost airline from Bangkok, Thailand, to Ho Chi Minh City, Vietnam, on 2 September when she began feeling ill and "dizzy" due to a stench in the air, Fox News reported.

Keng quickly detected the source of the disgusting smell — the male passenger seated behind her. She took a video that showed the man's bare feet propped up on her armrest.

She used a menthol nasal inhaler to try and block the smell of the feet, to no avail. Keng signaled to a flight attendant, who promptly told the man to remove his feet from her armrest. The man complied, preventing some in-flight vomiting, but not an unforgettable stink for Keng.