Is it possible for merchants to steal sales?

Of course they can. There needs to be a trust circle when it comes to affiliate marketing..

1. Affiliates
2. Network
3. Vendors

Either one of them can screw each other over and that's why a trust worthy affiliate network will also screen their affiliates and vendors.

One of my vendors has a faulty affiliate system, so I know not to use it. I wonder how many affiliate suckers haven't tested it? They're leaving money on the table...

I am talking about stats. Is it possible for the network to show impressions and clicks but not sales. Arent these stats realtime? So when a sale happens it should get recorded.

Anton,

There are tons of software choices out there, so your question is far to vague to be credibly be answered.

People can cheat at just about anything in life.

Even when using third party software to track sales (like Clickbank) the vendor can perform certain actions that some would classify as cheating the sales from affiliates.

For example:

I promoted a good product in the self-development field and send the vendor hundreds of subscribers to his email sales funnel. I signed myself up as well because I wanted to see what the funnel looked like. A few days later the vendor sent a sales email that offered me (and all the affiliates I sent them) a special discount link to purchase the product. The only problem was that they used a new affiliate code in said link, which meant I would not be credited with any of the sales.

The vendor said it was a terrible mistake and made it right with me to his credit, but things like that happen. It's life. Stay positive and focus on good end results and you will find yourself more successful than approaching life with fear and distrust.

If you expect to be ripped off, that is the reality you will find yourself living in.