Software, I don't understand the software list. Options

[gipsiad]

Looking at the software on this site and others I don't understand the problems with shareware or freeware, I don't understand what a commercial free update is, if you where to download the demo and the commercial update would that then mean you would have a compete program? The only thing I do understand is demo.
But what I want to know is why there isn't much in the way of freeware or shareware for the MAC like there is for the PC.
At the end of the day some people use these programs to make money and that is there livelihood and for others like me who will never be good enough to be a professional it's just fun and a good pastime as a hobby.
But being in the latter section means that spending $1000 for logic pro is out of the question I would never be able to save up that amount of money and by the time I did the next version of the software would be out and 7 would be outdated form 8, if you understand my point is.
For people who are not in the music industry but want to maybe play with music software how a kid would play with computer games, the price is too much.
This is why I am looking for free or shareware, I don't agree nor do I want cracked software doesn’t do anyone any favours.
But why can't for all the people who just using the MAC and there setup for bedroom mix's be able to share software with each other and if so where can one find such a site?