Popi, I'm so glad you posted this! I couldn't agree more. I've been thinking the same exact thing for a long time but never thought to start a thread about it.
And while we're at it, IMO what's even worse is a For Sale post with no pictures and no description of the condition of the item(s) up for sale. Sometimes there's not even basic info like whether it's new or used!
A potential buyer should not have to contact the seller (either via a reply to the post or a separate email) to ask for a description of the product when pictures and a few extra words in the ad can do the trick. No pictures and no description equals no interest from me!