vjmehra,
As I hope you realise, there's a lot of nonsense on this thread, but the basic economic argument is reasonable.
The underlying answer to your question is YES, you can get your PPL on a twin. I have a friend who did just that, and went on to go commercial and get various turbine type ratings without ever having SEP on her licence. Of course, there was a catch. Her husband owned a MEP aircraft, and was an instructor :-)
Without that little quirk, it really doesn't make much economic sense.