It totally depends on the company.
Are you referring to IT consulting firms? In this case, coudl you tell us the names, so we can give you better guidance?
Moving on to your 2nd quetion, regarding people with engenieering or tech background, again totally depends on the firm. You have plenty plenty of those profiles in MBBs and 2nd tier companies -actually, along with people with a business background/education, are the most usual profiles-.
This said, their job descriptions -those who are general consultants- is the same as for the rest, and they do the same type of engagemets.
Hope it helps!