Doing so would encourage passengers tocheck their baggage so screwdrivers, knives and sports equipment can ride where they belong: in cargo holds inside checked and TSA-screened bags.
TripAdvisor's app has a built-in baggage fee estimator: Tell the app how many bags you plan tocheck and whether you have elite status on any airlines that would waive bag fees and it builds the fee charges into fare quotes you get.
There could be better, faster check-in, more or faster security lines, and airlines' ground handling companies could be incentivised to improve baggage handling speeds.