I think the problem is that the different groups, while hearing the same words, actually get different questions.
For the first group the interpretation is more along the lines of "do we need software patents to protect our innovation/investment" which we know we don't.
For the second group the interpretation is probably more along the lines of "given the current situation where ideas can be owned (intelectual property), do we software patents to cover previously incovered aspects" which to them is almost certainly true (there is always some holes or inconsistencies they rather have fixed).
I am not ruling out that some lawers are in it for profiteering, but for those who are not it might be a simple matter of closing a hole in an existing framework.
Something that engineers can relate to but fortunately for us we are sometimes given the option of replacing a broken framework. Something that lawers almost never get due to the lack of political will to change something established.