Sign permitting is a very frustrating topic.
Our company does business in a lot of areas across Oklahoma, Texas and some points even farther away. We check sign codes and permitting requirements when the project is in the initial design, planning and bidding stage. Selling and building a sign first and then worrying about permitting later would be a foolish chance to take, especially if we're sending a crew a considerable distance to install the sign package. We will not install signs without the proper permits unless the local sign code allows us to do so.
If a customer wants to install something that violates a local sign code we might consider giving the customer the option to install the sign himself if the sign is something simple, non-lighted, temporary, etc. But the customer will understand up front he takes on all responsibility if the city takes action against his non-compliant sign.
I do not like seeing businesses and sign companies installing signs without permits. But it's easy to understand the temptation. Some cities and towns make it a real PITA to get a permit. They add in all sorts of extra red tape and fees to make sign projects less profitable or not even practical to consider at all. It's like a back-handed way of banning some types of signs without explicitly doing so in the sign code. Nevertheless, I feel that if our company is following the rules our rivals in this region ought to be doing so too.
When some companies bypass the permitting process they risk making matters even worse, politically speaking. There's already a lot of areas around the country where city councils, town fathers, etc have waged war against signs. Just like some upper class neighborhood associations have their design covenants on how all the houses should be painted many of these same places have pushed that "beautification" ethic onto the main commercial arterial streets. They ban entire categories of signs and then cover up what little signage can be installed with lots of trees, bushes and other landscaping. That fad hasn't hit every city and town, but it's a growing trend. If some sign companies or businesses doing DIY signage are sneaking around installing whatever they want without permits then they risk igniting political backlash. It doesn't take too awful much to inspire a few city council people to get on an anti-signs kick.
Oh, like others here, I really can't stand it when a given city or town has selective enforcement of sign code standards. We jump through hoops getting a permit but they don't do anything about another sign company installing stuff without a permit. Some of that gets into "good 'ole boy network" local politics.