And it is obvious that major internationals on both sides will be the ones that benefit most from the cuts in government regulations proposed by TTIP. So a substantial portion of the economic growth will go to them. Therefore I don't think you need to be in the tinfoil hat camp to support the believe that they are lobbying for TTIP.
The mistake that our EU leaders make, IMO, is that what's good for the EU's economy, is not necessarily always good for the majority of its citizens. Those government regulations were there for a reason, for instance to protect the environment, support area's who are economically behind etc.