I am an author of a library [1] that does this. I understand the what the OP is talking about and agree with it, but like anything for me the rule is "(1) Don't do dangerous behavior X. (2) If you are an expert, do dangerous behavior X sparingly and with caution."

Mind you, my library does not connect to a database, or any such crazy thing. It simply creates a singleton which is then useful throughout your application. There would be very few cases where you would not want that singleton and you would want your own instance. If so, you are free to completely ignore the created singleton and make your own instance. The creation process is also idempotent, except the data you put into that singleton; that data is a special case: it is your explicit responsibility to namespace it, which is indeed the whole point of this library. I feel pretty good about this thing.

[1] https://github.com/ipartola/groper