you have a valid point about paid and opensource softwares and I personally think that if you are using even an open source software for your commercial use you should give credit to the programmer on your site or donate some money to him to encourage him. Also big companies or people who have critical applications have a tendency to choose commercial softwares due to its CONFIRMED technical support as they paid for it. For open source you are dependant on the community when you are stuck somewhere. so I will still give credit to the author to leave good resource for those who may want to use the commercial one but I will also recommend him to post the similar article based on the opensource one.