If i make a program thats 3MB i will be proud because i know i did alot of work
That's no way to measure. I could easily find a way to make a 5MB exe with only a few lines of code. Did I work hard for that?

Or rephrased: if you can write two programs with the same amount of work that do the same thing and one is smaller, would you like the bigger more because you feel like you've done more? You have not, so the smaller program is better.

And as already said, as a programmer you serve the public, not the other way round. You must meet the requirements of the users if you want them to use your app. Only M$ can get away with not doing that.