It's poor etiquette and it may even be slightly disrespectful, but it's not against the rules in any way. People most definitely can turn a profit if they choose to, but seller beware as doing so will likely burn some reputation.
@Velocio started
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It's poor etiquette and it may even be slightly disrespectful, but it's not against the rules in any way. People most definitely can turn a profit if they choose to, but seller beware as doing so will likely burn some reputation.