False. True steel shops will use a red oxide primer, but there is no reason to suggest that it's crappy. We use an extremely high quality red oxide (rust) primer. Very similar to rustoleum, in that it inhibits rust, and binds to rust, it also makes a very good primer coat. The Reason that rust-colored primer is prevalent in the industry is for multiple reasons. One, it effectively covers any little bits of rust that can't or don't need to be removed. Two, momentum. People who have been purchasing products from the steel industry expect the red oxide primer, and consider it to be a "professional look". People who have been buying steel fabrications for 50 years want to see what they are used to. The alternative atm is gray, but most people confuse that for a bad coat of paint. Third, the red oxide is very easy to see through coats of paint. So, if you get a bad coat of paint, it's really easy to see the red, and know that you need to reapply, or sand and start over. The red stands out against most colors (since almost nobody wants rust color as the finished product), and allows you to assure even and full coverage.