Dividends are taxable, and they're often paid to entities that are unable to structure "profits" as carefully as the largest corporations can. So, in this discussion in which everyone (even Jeff B!) seems to agree that more taxes should be collected, dividend requirements would be a way to do that.

Of course, that's too tame. We'd be better off eliminating the most common forms of incorporation, or severely curtailing them e.g. maximum revenue limits. All the things that corporations can do, individuals, partnerships, mutual-benefit firms, etc. can also do, except often more carefully.