I'll try to clear up some confusion.
Am I right in saying that you are allowed to post links, if it is to a non commercial site.
Yes, that is correct.
See here: RULES for posting on the SANParks Forums
14. You may not advertise or link business sites on the Forums. Only non-commercial websites may be linked to.
Some members post links to personal blogs and photo sites which is fine.
What is commercial?
When is a link commercial?
A commercial site is a business site, a site which sells something.
And you are allowed to post commercial names.(Like PnP or Spar or maybe Frikkie's Panelbeaters)
But no link.
Because this forum is also one giving information to members, you are allowed to give advise about the best car rental company, where to do shopping on your way to the park and such. No links are allowed for the reasons explained earlier in this topic.
You may according to the current rules post the name of the company but you may not link to their website. Spammers register here all day everyday and that is what they do, they bombard us with commercial links. If we allowed members to post these links too, how would we be able to distinguish between what is helpful and what is just pure spamming? I fully understand that you only mean to help but unfortunately if we allow it in one topic, we have to allow it all over.
Frikkie's Panelbeaters might be frowned upon unless it is directly relevant to information given to other members, information relating to a visit to a SANPark.
What is spam?
The fact that you are asking is a feather in our mods' cap because it shows that we are doing our jobs properly.
Spam is a post which is made purely to publish commercial links. A spammer is a guy who registers on this forum with the sole purpose of distributing commercial links. Spammers never contribute anything positive, they just feed off this site and are not welcome on most sites on the internet.
We at times also get legitimate members making a mistake by posting a commercial link but that is a forgivable mistake and easily rectified.
The downside of having such a successful website is also that it is a very high priority site for spammers. Successfully getting their links here kicks their Google ratings up high. Some mornings we have to delete a list of them before our morning coffee and we are continuously scanning posts and new members for possible spammers. Fortunately we have a few tools in our kit to distinguish between genuine members and spammers.
Hope that answers your questions.