Possibly most people who are regulars on the forum and answer questions for others, but NOT the OP. Hence their asking about their options.
If you want to advocate for the courtesy of asking before conceding, you can phrase it like (italics used to indicate my changes to your original statement):
"You can concede without penalty, however, I think it is courteous to ask your opponent if they are ok with this. If they say no, then the game will go on after your travel and you hopefully won't have to worry about being kicked out."
Your statement implies the OP needs permission to concede or else there will be a penalty. It also assumes that just because a player says they don't want you to concede means they won't change their mind about kicking you out at some later point. Hopefully they wouldn't, but the OP should understand that leaving the game going puts them at risk of receiving a penalty if the other player decides to kick them. Conceding ensures no penalty. The OP can then decide what risk they prefer to endure.
To phrase it as you have done is more than advocating for your agenda - your statement misleads people into believing they need another player's permission to concede without penalty. Whether you agree with the moral side of concession does not justify you trying to force others to behave as you want by implying things that aren't true.