Why are they so small?

This morning on my way to work I heard a loud popping noise. I thought that it might have been my tire but I was going about 65 and my car didn't swerve or anything so I figured it must have been something else. When I started to slow down I knew that the popping noise had definitely come from my car. I parked in my teacher parking stall,(I'm pretty important) got out of my car and sure enough, my back right tire had blown. Luckily my rim was ok even though I had just been driving on it at 65 MPH. I didn't have time to worry about it right then so I just tried not to think about it till I got off. I went out after work and discovered that my spare tire wasn't only the size of a bike tire but it was almost flat. I found a teacher at the school that had an air pump and we filled it to the max. I got a few looks as I walked around the halls with a spare tire under my arm. I replaced the tire, which was easier than I remembered. I had a lady pull up next to me and ask If I needed help. I told her I was very capable of changing my own dang tire. I was nicer about it though, but seriously? She was a nice lady so I shouldn't say anything. Anyway, I think I was more scared driving around on that bike tire of a spare than I was about driving on my rims. Who the H invented spare tires?! Can't they at least make them look kind of like a real tire? I felt like an idiot driving around with that thing on my car! I felt like I needed to park it next to a dumpster or a large tree to hide its hideousness. I shouldn't talk so bad about the little guy, it's not his fault. So I'm calling on all automakers to reform. I know that we're in an economic crisis right now and that all the CEO's are begging for billions of dollars to keep their companies afloat but c'mon guys, how hard can it be to give spares the respect they deserve?