Vril is happy to maintain the status quo of the universe because its getting him paid. If he went around destroying bad guys for free he'd have no clients but if something threatens that merc business like starro or black lanterns he will fall on the side that will be in his long term best interests. For example, Starro could give him money to leave him alone but Vril will see his L.E.G.I.O.N contracts as worth more in the long term. Of course Vril isn't just about excessive money, he's clever, even if Starro sets him up for life its Starro. What is stopping him going back on his offer after he controls the rest of the universe? He's a complex fellow, is Vril.