Sounds like there are two different things here...
1. If the sign is yours: Dave is right... do what you like. If you want to do a full nut-n-bolt restoration or leave as-is that is entirely up to you, but just remember what you have at the end of the day is yours and nobody else can change that.
Also building off of what Dave said...as an example (this is adding in my opinion
), a Deusenberg (or rare sign) should be meticulously restored
or preserved because of what it is and the history behind it, but a regular mustang (or common sign) maybe not need so much in the way of a detailed resto. <--Some may disagree, but I'm not taking into account the numbers matching factor, etc, etc....
2.The person mentioned is running a business. To get more bang for their buck they might opt for a lower quality restoration rather than going all out, but it depends on what their end user is looking for. Sounds like they are targeting different audiences and can bring higher/lower quality stuff according to venue too. At the end of the day its business.
Not sure if that helps or not, but just adding my 2cents worth
Thanks,
-Paul