No worry about being gross. This is a very common occurence among people flying.
One can prevent it to a certain degree in that one carefully refrains from certain foods 24 hours prior to the trip:
avoid onions or any other food known to cause flatulence like cabbage, beans, leek, etc.
avoid drinking any "fuzzy" beverage before the flight like mineral water, coke, beer, etc.
ask your doctor for a medication that controls flatulence.
in the worst cases, try to have a thorough bowel movement right before the flight.
one good product is also natron or baking powder, mixed in a little water. Vile to drink but causes wonders.
There is no excuse for a passenger to let wind at his seat. There are lavatories on the plane that can be used