...Isn't PAlib under GNU? It shouldn't have a price tag.
I do not know if this is using PAlib or not or what the licensing of PAlib is, but I would just like to state that the GNU GPL and LGPL licenses do not forbid adding a price tag to a product in any way. Of course, upon purchasing the product, the source code is freely open and available, meaning that one could theoretically pay for the product and then release the rest of the source (as long as this source is similarly licensed, which it would be in the case of the GNU GPL, at least, as those are the terms of that license for derivative works).
Just for clarification: the GNU GPL and LGPL licenses do not require that a product be monetarily free (as in "costs nothing"); they do require the freedom of freely available source code, but it is perfectly legal for someone to only make the source code available if the product is paid for. Of course, once the product has been paid for, the customer has the right to then modify the code and then freely release the
modified version for no cost.