Joy Hawkins asked in a Local Search Forum thread if Google will filter the gold stars shown in the organic search results for local results for specific industries. She said she can't get the stars to come up for specific industries and she is wondering if Google filters them out for specific types of industry queries.
Tim Capper responded that he asked Google's John Mueller (he didn't share the source of this conversation) and John said they do not filter by industry. Here is what Tim wrote:
Just asked John Mu and he is not aware of any filter being applied to industry. He did say that they don't like if the review markup is sitewide or on irrelevant pages. Also they don't like if testimonials are used within the markup.
There was a time where Google would not show local results for SEO or web design companies back in 2009, but it came back a few years later. So it isn't too far fetched to think there might be a gold star review filter.
I do see gold review stars for my company:
Forum discussion at Local Search Forum.