It has been a "tradition" from new users that make them misuse the word flyer.
The word flyer or pamphlet is a form of paper advertisement intended for wide distribution and typically posted or distributed in a public place or through the mail. -Wikipedia
The point is, people uploading planes called "little flyer" or "good flyer" is a foolish idea for a website like this.
You may be right but alot of young users may not understand grammar or even dont speak english so it is the best word they can think of at the time. Just ignore it :)
Its also pretty foolish that you care so much :/ Just being honest bro.
Actually:
Flyer:
1 - alternate spelling of "flier"
2 - pamphlet
Flier:
1 - a person or thing that flies [ie "nervous flier"]
Therefore: these "little flyers" are perfectly fine according to the Oxford American Online Dictionary.