Giving alms is a personal call. Sometime it's very difficult to differenciate between honest real cases or just outright sham.
Just know this, as long as you are the giver, you should be at peace with yourself when you give, cause you are not in the sin for doing so. If you give wholeheartedly, you shouldn't be thinking back on your actions. Thinking about it will mean you did not give wholeheartedly, thus by religious context, you will not gain any spiritual merit. So might as well not give, even if it's real cause.
So that said, it does not matter if the alms collector is real or fake. Cause the sin is on him if he not for real. Worst still under the pretence of religon, it seems to me like a very major sin.
On the bus drivers, they are only human. And their jobs these days are more demanding. Last time the driver only job is to drive, there is a conductor who will handle the passengers and collect fare. Now with the "advancement" of technology, not only does the driver have to drive, also have to handle passenger's query, operate an increasing number of electronic gadgets, and collect fares for coins paying passenger.
I have just one thing to say, anyone who bitch about bus drivers, become a bus driver, maybe for a week. See what tune you will be singing later.