It's not offensive, it's just sort of incorrect. Most people date and marry those in the same age and socioeconomic bracket. You are greatly exaggerating the socially condoned differences.
Like any partnership, both parties bring valuable things to the table, some of which are less quantifiable and tangible than height and money - organizational and management skills, social benefits, etc. Depending on context, the partner with less physical and monetary power may still be the stronger party in a relationship. This is where trust and honesty and a will to please the other, rather than just take what you want, come into play to keep the power balanced and the relationship healthy. Any sufficiently imbalanced partnership, romantic or otherwise, is doomed to eventual failure.
Like any partnership, both parties bring valuable things to the table, some of which are less quantifiable and tangible than height and money - organizational and management skills, social benefits, etc. Depending on context, the partner with less physical and monetary power may still be the stronger party in a relationship. This is where trust and honesty and a will to please the other, rather than just take what you want, come into play to keep the power balanced and the relationship healthy. Any sufficiently imbalanced partnership, romantic or otherwise, is doomed to eventual failure.