I wouldn't limit to OUSA members, plain club's members are contributing by starts and receiving services as well.
A hard question to answer without comparative statics and counterfactuals. All things being equal, $175 and orienteering exists in the US? A bargain.
Setting aside the question of how effectively OUSA has been spending money in the recent past, I think it would be fallacious to evaluate OUSA performance purely based on what services it manages to provide to OUSA members or to larger group of members of OUSA-affiliated clubs. OUSA has a mission to spread orienteering far beyond either of those sets.