Basically, brokers are going to function like any other business: if you want to develop a successful business, you need happy return customers. So any broker that's looking to stay in the market for the long term is going to have to maintain good business practices, because otherwise they will lose clients and they will gain a bad reputation that will prevent them from getting new clients.
Of course there are differences between how customer friendly each broker will be; but the basic rule is that scams don't last long.
I doubt there is a rule for 'functioning' in all businesses across the globe. Brokerage is business of scale and in FX you compete against huge fair established institutions. It is hard to make money for a new broker, that's a fact. We might discuss how a trading desk generates income and why 'real inter bank access is slightly different thing. It is not scam, that's usual practice.
Additionally it is not about 'friendliness' , it is about fine defined stream of revenues, nothing else. Finally I mentioned the 'insurance character', it is not only the brokerage, it is about the local environment of the physical location of brokerages.
I believe there is a need to ensure fair practices and the service idea as driver of business is not good enough to me. It might be to you os you should feel free to take the brokerage of your choice.
And finally scam work sometimes long enough and history is full of scams. So I cant see the assumption that 'brokerages' per definition have guarantee fair process because they want to keep the customers as valid argument.