Hello Lech,
It does do it on the demo.
See this screenshot https://www.dropbox.com/s/rn0389ruzshgc9t/menu-responsive.PNG?dl=0
This is the bootstrap default styles for responsive websites.
If you want to modify the Bootstrap styles you can use the following CSS styles.
@media (min-width:992px) {
.container{width:100%;}
}
I tried this using Firebug and it allowed more space for the logo and menu to be on the same line.