It is a very subtle way of making yourself look more influential than you are in reality in a number of ways.

First, if anyone has the sockpuppet accounts on level 0 (directly on their trust list), or on level 1 (trusted by those on your trust list), then your ratings will show up by default.

Secondly, and more importantly, it helps certain stats that make it easier to account for a "DT1" member keeping you on their trust list (and would booster the argument for a "DT1" member to add you to your trust list -- or booster the argument for others to add you to your trust list). If you look at the trust dump alone, you will see that more people have lauda on their trust than is truly accurate to say. The accounts were created over a fairly large time period, and it would be fairly difficult to spot without the cumbersome, time consuming process of looking at each of the accounts manually (it would be difficult to spot the fact these accounts are all sold via automation).