Just to clarify - I'm not advocating 'never use Rails' or even 'Sinatra should be used more often than Rails'. There are trade-offs, to be sure. I definitely agree with your points about 'limited resources' and 'saving time'.

I just feel that people tend to pick these big frameworks, even when they don't need them. They just don't think about it and often dismiss these simpler tools. This talk came from someone saying to me 'oh, I started writing this <small-app>...'. And he spent the whole weekend basically just configuring all his chosen tools.