Now don't obfuscate by simple-thinking...you know it's more complex than that..
Keyword: largescale. When we are talking about a LARGESCALE shift in energy production with widespread and centralized plants of solar/steam, we're talking about MAJORLY cutting into BigOil profits...
THAT is what they are up in arms about. They aren't worried...per se...about Joe Backyard power producer...yet..but the real implications are that BigOil doesn't want a power type that cannot be easily manipulated.
Refining crude into a useable source of energy for say, cars, is a complex process that neither you nor I can replicate in our backyards. In fact, refineries are tightly-controlled operations. Anything tightly controlled and complex to produce is subject to the dangers of price fixing via a monopoly.
Steam generation is like child's play...anyone can do it with a fresnel lens, water and a generator which is propelled by a directed flow of steam. That's it. Even if BigOil erected and controlled large producing and distribution centers of steam energy, they couldn't fix prices like they do now. If they raised KWH high enough, Joe Backyard could start up his own neighborhood power station with ease. This cannot be done at all with nuclear, coal or oil refining/conversion to current. And hence BigOil's pushing of these exact types of dirty and dangerous (read: complex) forms of energy production.
It's the POLITICS of alternative energy that's keeping it from happening. BigOil runs politics. Although, Kudos to Congress recently for standing up to their shortsided and stupid hopes to drill for the hard-to-refine pittance that exists on US soil.