What’s the deal?
People like WordPress for many reasons, including ease of use. Often, the large number of themes and plugins available are given as reasons also.
Recently a number of authors have begun debating the benefits of premium themes and plugins as opposed to the free ones. There are lots of good arguments on both sides. Rather than repeating what others have said, this post will simply summarize the arguments.
Use Free Themes and Plugins
Free is always good. Also free themes and plugins offer a great way to develop a new WordPress site without spending a lot of money.
Use Premium Themes and Plugins
Unfortunately free themes and plugins do have their downside. Many free themes have hardcoded links promoting the theme authors or other items. I don’t object to a theme author getting publicity in exchange for my use of the theme; however, some theme authors hardcode links to other sites–many of which are objectionable. Sometimes these are hidden so users won’t see them, but search engines will. Some themes also have encrypted code hidden within them. We have no way to know what this encrypted code is going to do! Plugins, naturally, have the same issues.
Another argument in favor of premium themes and plugins is simply support. If a free theme or plugin author decides to no longer support their past work, you’re out of luck. This is much less common for premium themes.
Use Theme Libraries
As a compromise, consider using a theme library or club. For a fee, you gain access to a fairly large number of themes. This avoids the cost of purchasing each theme individually.
This post will be updated with a few related articles (from elsewhere) as I get time.