[tmikaeld]

I think it is the fact that some companies create crippleware open source project where parts of the core are open source and additional key parts are licensed under a sub-license that requires payment. Also, MIT and BSD doesn't enforce you to share added changes, fixes or additions to a project because of this - thus, hurting the open source community by the project not gaining (possibly) important or significant changes.

From a company standpoint, this makes sense if the parts are large and costed a lot to develop. Some companies eventually make these parts available eventually, some don't though - possible because open sourcing something that you initially charge for, could piss some customers off when they realize that they could have gotten it free.