There is no secret. They told you the reason and accused you of spamming. Because other's have gotten away with it only means they have not been caught yet.
WARNING not only is it against the TOS but MySpace in the past sued several affiliate networks AND affiliates themselves $500 million because their affiliates were posting affiliate links.
I blogged about it here:
Myspace 500 Million Lawsuit Against 20 Ad and Affiliate Networks - 5 Star Affiliate Blogs
So you NEED to be aware when you spam that when it's against a company's TOS (like MySpace or others)
the network could can you and EVEN WITHHOLD all your commission if it's also against the network's TOS. You can be certain that if networks are worried about being sued they are adding don't spam MySpace to their TOS and punishing affiliates that break the rules and could cost them MILLIONS!
Break the rules and risk doing all the work and not getting paid!
Market with integrity and everyone wins!