This saying is primarily used in real estate and means that it’s all about the location of the house that gives its value, same house is worth less in a bad neighborhood and it’s valued a lot more in a good neighborhood.
Same goes for a glass bender, you will do a lot better in the best of cities.
My advice to people that are planning to sell neon,

if you already know how to bend glass and make neon and are ready to sell it, before you start advertising and investing in your city do a bit of research and find out what the level of the amount of money does your city have. And by the city, I mean the businesses in your city, and if you see that your city is not wealthy the possibilities of not selling are high.
This is a standard practice in large businesses, large businesses like Walmart, I Hop, Costco etc.don’t just invest the millions in a building and inventory blindly, by the time they decided to start building they already have researched the city and population to see if the people have enough income to be able to spend in their store, they even have an estimate of how much they will make the first year even before they lay the first brick.
And that is because they did their marketing research, same should be done with any business, you may not have the thousands of dollars to hire a market research firm but you can do your own research, just by knowing how the businesses in your area are doing, and you do that by either asking the owners how business is doing or just by looking at the businesses, mainly the small businesses, you can tell by the amount of people buying at the best day which is usually on a Saturday, if in a Saturday you see an empty store then you can be sure they are not doing very well, or if you see that they are not taking care of the building or the existing signs, those are signs that they don’t have the money to do the repairs.
So don’t waste your money in a place that will probably not buy your neon.
In most neon shops there are two kind of incomes, one is from new neon signs and the other is from Repairs or service calls, and it used to be that there was also the neon made for other sign companies.
So a good business practice is to give priority to what brings more money in, in some cases it will be the repairs, because repairs will bring the almost daily flow of money because repairs are sometimes fast and for that reason you get paid fast, making new neon signs would probably bring in a larger amount of money but it takes longer and making neon for other sign companies is right now very sporadic.
So it depends on where you establish your business, if you are in a city with a lot of money you will not have any problems, some people complain that cities which have a lot of money are expensive to live in, and it’s true but those cities are where the people and businesses have the money to buy.