Ehhh, marriage is like the market. Always changing, adapt or lose, sit on the sidelines of married life till the trend moves in your favor. But, this time it's different (new women). We know where that thought gets ya. Frankly though, my wife is smarter than me, on the flip side she thinks the same about me. I dump shit in her lap and say "here ya go". Then other times I say "Gimme that" you don't know what the hell you're doing". We have a blast, I could say "I'm lucky" oth isn't that what all people say who work at something with success.
When you get into your fifties and sixties you're going to wish you had a companion to relate to. See Sinbads latest routine on Comedy Channel for some quirky insights into it, esp the bit about the strokes.
Why marry ? You can relate and have a companion anytime you want to or any time you are ready for it.
Of course you're right. Alot of things are just culturally ingrained rituals, every holiday we have can be done w/o, but thats life. Companionship is voluntary but with or w/o the marriage ingredient companionship is a good blue chip long term investment.