There aren't any for most people, unless you know what you are looking for and have some assets (ideas, sites, knowhow) to throw at them. It takes a unique blend of skills to make it in AM and there arent' to many folks with all it takes.
Consider it only takes $10,000 per month in payouts to be a CJ "Performer" which probably means that is the top 1% or less of affiliates in the biggest mainstream affiliate network.
Just look thorugh CJ to see where the cash is flowing in mainstream inustries.
There are lots of companies with AMs that did (or still do) something that is not AM and don't know how to answer even the most basic questions or provide basic support needed for an affiliate to promote their products. Some who don't even bother to answer email when the program first launches.