I added some color for you. Misconfiguring a node with some ridiculous maxconnections (running it wide-open) is possible, and even a nice thing to do if you have unlimited bandwidth. It's also nice to tip your waiter $500 when you go out for lunch.
Allowing more users == misconfiguration for you? That is not correct and the data that I've provided fits (50-80 connections). The analogy does not fit either. lots of RAM to store incoming transaction 
This depends on min fee parameters.