It's just so easy to play another game of chess that I have no idea why a person who loses a knight for nothing is doing anything wrong in resigning and moving on to the next game? Just play another game
Some people


in this case your opponent was probably disgusted with himself for throwing away a knight and didn't want to embarass himself further.
Outside of that, one should play thru a chess game until he / she doesn't have a "reasonable chance" to win or draw. Even the great Samuel Reshevsky who was in the top 10 in World for a long time succumbed to Stalemates when ahead. Check this one out against Larry Evans. Reshevsky said at end of game he thought Grandmaster Evans was extending his hand to resign, when actually he went to grab his Queen on Reshevsky's back rank to sacrifice it. Then that was followed by sacking his last piece his Rook for the Draw !!!!! http://www.chessgames.com/perl/chessgame?gid=1252040

But the knight he lost was the first piece down, we both had over 25 minutes of time left. If someone doesnt want to improve their game fair enough, it's only benefitting other people's ratings, as well as denying themselves and their opponent the chance to learn and develop as players.

Im not complaining at all, I just think that this guy, if he/she was serious about their game, they would continue surely?

Really Dude???
You ARE complaining. You're going on about it being frustrating.
It's within your opponent's right to do so.
If I realized I'd just dropped a whole piece like that with lots of time still on the clock, I'd resign and move on to the next game.
Why are you wanting to make a big issue out of it?

But the knight he lost was the first piece down, we both had over 25 minutes of time left. If someone doesnt want to improve their game fair enough, it's only benefitting other people's ratings, as well as denying themselves and their opponent the chance to learn and develop as players.
Would you play a piece down in a long game if you dropped it by mistake realizing it only in the last second when you let go of the mouse button? Or even give your opponent piece-odds in a slow game?
Ive just won a game in which my opponent threw away a Knight for no apparent reason and then resigned, while still having 29 minutes on the clock.
I tend to play the first player that a challenge throws at me and more often than not they are near or around my relatively lowly rating, which I would love to improve so I shouldnt be whining, however I would like to have a proper game and win on my terms.
Who else feels as frustrated as I do when opponents on Chess.com resign like this, despite having won a game?