Yup, these companies call you if they are interested in your service. I have received inquiries like that from Sign Resource from LA & Pattison Sign Group. Asked both of them how they did find out about us and both of them said - simply google search in your area.
On another note, many companies have contract with other companies and sometimes it will look funny price wise. For example, our company was installing 3M frosting to new bank location for all offices, but exterior signage & exterior decals were installed by company from Manitoba. ( So they had to drive their crane/lift to Saskatchewan, which would be pretty costly)
So its all depends, and most of the time there is nothing you can do on your end to get the work, so do not stress to much about it.