In re: Sale/purchase of tickets.  
It is completely legal for political parties or authorized functionaries thereof to sell tickets.
However not giving a ticket after taking money/other consideration & refusing to return it would amount to cheating.
It's a different matter if it was made clear beforehand that the money/other consideration was either fully/partly non refundable.
That said, there could be tax issues for all concerned if everything is done in cash.
Unfortunately, the cash for tickets market hasn't been formalized or regularized.