then you should've said jack base. but my point is still relevant, pointing that out serves no purpose in the thread. it'd be along the same lines of: hey, i see you have old tires, i have some i just took off are you interested? what purpose does that serve?
and yes, i would consider it improper to interrupt a conversation that was already in progress to ask a stranger if they wanted a jack base. because that's what a thread is, it's a conversation.
so again, tell us all how that this is a limitation? is it the persecution that you can't freely insert yourself into the conversation with a non sequitur, thus junking up a thread? is it the annoyance of having to send a DM? is it because you want to do so publicly so that there is an appearance of being a "good guy"?
i guess the question eventually becomes: why does it concern you so much?