I count 5 different 3.5mm jacks I use on a regular basis (work headphones, gym headphones, car, girlfriend's car, home stereo). Now I need to buy 4 additional

I count 5 different 3.5mm jacks I use on a regular basis (work headphones, gym headphones, car, girlfriend's car, home stereo). Now I need to buy 4 additional adapters from Apple for $40 or carry an adapter with me everywhere I go?