Yes, even it would be only small investments that will make sense. It's also a challenge for those people that had small amount and wants it to grow. And I believe that big things are coming from small ones and once it started to show it's success that will end up to grow. Think about you'll start an investment with big amount and suddenly you'll lose.
There is no such thing "big things are coming from small ones", in other words, you said you will be able to make 1 btc profit from 0.01 btc investment? Try it.
There is also no such thing "an investment with big amount and suddenly you'll lose.", unless you were invested your money in HYIPs/Ponzies sites.
When an investment offers great return it is normally a high risk investment but your performance really matters a lot because if you know what you are doing it will normally bring good results.
Ok. You are are small risks investor which is good for you. So it really depend on individual I guess. Those individuals like you only want a small investment so its sustainable. While others are risk takers, getting big investments for big returns. Its also up to the individual how much money they can loss as well.