Ajzen and Fishbein 1980

The key difference between Hunt + Vitell is that H+V deal with ethical issues.
Ajzen and Fishbein look at the attitude/behaviour relationship.

H+V look at the ethical judgement made as a combination of deontological and teleological evaluations . These judgements form intentions that then lead to behaviour.

With the Theory of Reasoned Action does not explicitly deal with ethics.

Personal Attitudes (based on beliefs)
Sujective norms (based on normative beliefs)

These peronal attitudes and sujective norms combine to give intentions and then behaviours.