First and Foremost:
We're crazy. With that said, keep in mind this one simple thing: 

It's a hobby.

This isn't any different than collecting stamps (read that as: collecting small squares of parcel postage) where currently the highest valued stamp is $9,500,000.00, or collecting art where a recent Banksy piece sold for $12,100,000.00. 

It's not that I mention these hobbies, or their prices to belittle them... no, rather, to sharpen the point  that objects mean something to us. The stamps themselves may reconnect you with your grandfather's smile. The art may unlock something deep in your heart and soul.  The rarity of an object may fuel a fire or fill a void. The result is often simple- happiness. 

Money is a means to and end. How many of you enjoy money because of the way it smells, or how it feels between your fingers? Would you hoard it in piles merely to sleep on its surface, day dreaming of its particular shape and texture? No, we trade this currency as an exchange of our time...for our happiness, for things that have meaning. Us houseplant folk aren't any different.

A houseplant may be thought of as a reflection of our care and attention,  often growing painfully slow, teaching patience and dedication. They are the manifestations of hard work and love. More than a purchase, they are the adoption of nature. A promise oneself to do good. With each adoption, a pledge to be better than you were before.

Houseplants may represent the beauty of nature incarnate, vesseled in our living rooms, reliant on our attention. They remind us of deeper truths: where we come from or where we're going, who we are, and what we're made of.

Botany Odyssey