If they don't have access to the server seeds, why shouldn't they? After all, they can just use another alias and you won't know.
It's called the appearance of impropriety. If something looks shady, some people aren't going to delve into the facts to find out if it's actually shady or if it's above board...they are just going to move on.
By ranlo actually using the username 'ranlo' at Moneypot, he is being totally transparent and there is absolutely nothing shady here.
Here is the stats :
https://www.moneypot.com/users/ranlo Public.
This is really silly. A poll on Moneypot owners accepting rain!

Edit.
Moneypot's stand on these matters is quite apparent.
MP owners can run apps, invest, play. And accept rain.
MP app owners can run apps, invest, play. And accept rain.
MP investors can run apps, invest, play. And accept rain.
MP players can run apps, invest, play. And accept rain.
By owners I mean those who do not have access to server seeds.
You don't seem to understand what I'm saying. I'm not talking about rain, who cares about fractions of pennies? I'm only talking about what I quoted you as asking, which is why shouldn't the owners play on the site. The answer is that it LOOKS bad, and may turn people off. It has the appearance of shadiness even though you and I know that everything is above board.