"A Problem Page For All!"

Wales, Ireland, Sotland and England all drive on the left, as well as Australia, New Zealand and there are some other countries too, but I can't remember them...
I don'#t really get why it's such a big deal: driving on one side or the other can't make THAT much difference can it?
And BTW, I NEVER want to drive in Europe, esp in Italy and Paris. They're world reknownd for having awful roads and a kinda free-for-all attitude when it comes to driving. In Spain, people don't put their handbreaks on because that way, when they park, people can move eachother's cars to create more room and stuff. How bizarre is that?! I was watching people moving cars and then reversing into the spaces they'd made and I thought they were all insane! lol.
Is it true in USA you only have a licence plate on one end of the car and you aren't allowed to reverse into parking spaces or something? That's weird too.
How come America is so bad at public transport outside of the big cities?