Now now. Law makers are typically business people and are bound to have personal interests in the law the propose. That is the reason behind multiple representatives. Chances are if a a law doesn't impact a politician they aren't going to propose it.
Interesting. In the business world, you would be obligated to abstain from such a vote. For example, say you were an owner of a furniture supply business, as well as a director or manager of a business wanting to purchase furniture. You would have to stay well clear of any dealings with furniture purchases.
That is just common sense. It avoids accusation of corruption or conflict of interest.
If I was a politician, and owned a car dealership, I really would stay clear of legislation directly benefiting car dealerships, let alone sponsor it!
Are things really that different in USA that this is acceptable?