Yes. Unfortunately such childish behavior does occur. There is some kind of computer "watchdog" that looks for repeated patterns of abuse and will issue the offender a warning or a short "timeout". If you got a message at the end of the game that said something like "Your opponent may have violated the Fair Play Policy", then the computer noticed it too.
Unsportsmanlike conduct?

Thank you, this answered perfectly my question, good to know that something is done to prevent the extended use of this conduct.
Anyway I don't understand why bothering playing chess at all, with that attitude.

Thank you, this answered perfectly my question, good to know that something is done to prevent the extended use of this conduct.
Anyway I don't understand why bothering playing chess at all, with that attitude.
Just to know, is it a break of fair play rules to stop playing in a game and let the time expire because down lots of material or a a single move away from checkmate?