snip
And along came the libertarian with his private-property ideals
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What you're advocating sounds something like a bazaar, where people are crowded into one place and try to speak louder than the next guy who's selling the same thing. Except in this case, one guy set up shop, and someone else came
into his shop and started advertising his own product--and wouldn't you know it, the guy in his shop has undercut the competition! Along came a third guy who undercut both and he's offering his product at a perpetual 5% off what those other two schmucks are offering. The guy who set up shop doesn't like it and asks the two to leave his personal space. I think he should have the right to set up his own shop and have a fair shot at having one-on-one attention with potential customers, rather than consistently battling the two guys who pushed him out of the way to do their own business in his own shop. Of course, if someone is looking for, say, gold, he might scan the board to see if there are any obvious threads selling gold. Otherwise he might use the search function and find threads explicitly about gold. There's no reason to cram all the gold-sellers (and people who are selling gold-based products, at that) into several related threads, as this creates a lot of redundancy (or what might commonly be referred to as spam.) Since each gold seller has their own shop, and are simply running around yelling "My stuff's better!" at every other shop, what you have in the end is a big mess.
One thread with one seller with the various products he is selling is much more preferable to me, the guy who doesn't want to shift through several user-created advertisements before finding the guy who said, "Well he's a great seller and didn't scam me" or "No he's a terrible scammer don't buy"; in other words, irrelevancy to the thread is what I don't like. The one advertisement by OP is just fine; when SirSpamsalot feels the need to post in every single thread ever created multiple times about his loosely-related product, I begin to think there's an issue. Though I like the idea of experimenting to find the truth of the matter, I do not believe this is a new idea, and we already know what happens when users are encouraged to advertise willy nilly on every thread they find. Though I am all for freedom of speech, there's a certain point between practicing that, and being a general nuisance--if spambots should not be allowed freedom to spam, I don't see what difference it makes when a person does it, since most people still don't like spam. I'm certain that many of us agree that, yes, we like our threads to be exclusively ours (just as many people prefer their partners to be exclusive, despite those who enjoy misogyny), and it is for this reason why we would encourage a certain standard; however, if most of us agreed that cross-thread advertising was a legitimate way of doing business, then I'm certain that's what we all would be doing already. I believe it's clear what users of this forum prefer.
So, it boils down to this: if the owner of a thread says, "Sure come on in and advertise all you'd like!", there should be no discrepancy as to whether or not it's okay to spam that thread; since the OP and the spammers are happy, it's a win-win. Otherwise, if not mentioned, it is generally assumed that the OP does not want spam, so please don't do it.