Sage says he knows 10 girls named Lindsay and it isn't even clear if he included the ones with restraining orders against him, so I'll grant you the name is not unique.
In fact none of the factors are totally unique but taken together they become unique. I wonder of Sage's Linsday's how many are addicted, immature, dumb, sleepover, feuding wolf howl loving Lindsays. That doesn't even get into the baby's complexion which is very similar to Lohan's.
E-trade, or at least the ad agency were clearly taking a shot at Lohan and any good lawyer would be able to demonstrate that in court. My guess is a settlement.