You would not believe the shit we pay for.
Were our company in need of a way to cross the street, we would almost certainly look for a vendor supported crosswalk, plus consultants to guide us through crossing the street the first few times, and training for our designated crosswalk guard.
And I'm not even convinced they're doing it wrong. People are expensive. Most the time Build vs Buy is a no-brainer for everything but your absolute core business, and even then you should wonder if custom software really will differentiate you from the rest of the market.
Honestly? I wish I had seen Storemapper a few months ago. We were in the middle of a website redesign and the board president decided he didn't like the map. He got the CEO involved who told the CIO who told... you get the idea. Storemapper would've been pure win that day.
At $19/mo, even if it only took me day as a developer to create my own, I'd rather just buy the service for a year. I'll get a more polished version, I don't have to maintain it, and I can go do something more productive instead since I'm not actually in the business of creating store maps, I just needed the one. If you don't have in-house developers, like a retail operation might not have, the value proposition becomes even clearer.
I am a former developer myself so certainly been there done that mistake myself.
Hire a developer with a salary, benefits, and tax to build this module plus project mgmt time for requirements building, testing, training, documentation, sustain, etc.
Pay $60/month and 1/10th of an FTE to plug it into existing assets and sustain it.
I implemented Storemapper for a few clients (indie sellers and major brands), and they absolutely loved it b/c it solved their exact problem and cost next to nothing.
However, the analytics piece alone could be worth $60/mo if it provides something that Google maps doesn't, especially with regards to finding out when/where searches happen for your stores (conceivably getting the user's coordinates, and you already know the context for their search because they're on your site's store map). A large amount of searches in a particular location might mean it's a good store expansion location.