Besides the above, which is completely and utterly true, legislators often want consensus, if they can get it (I realize how crazy this sounds, given the way bills often end up). They don't want to be forced to pick sides when it's large companies that support one side vs other large companies that support the other. Not just because of the lobbying money involved, but because they think they are trying to do the right thing, and if it's 25 folks they trust on one side of an issue, and 25 on the other, they aren't likely to do anything.