Yes, you can copy LibreOffice as many times as you like, and you can give away and distribute copies to anyone you want, whether for private or business and professional use.
In fact, the more copies of LibreOffice you give away to other people or install for them, the happier we will be. LibreOffice is a community project. If you like our software, please consider joining the community and getting involved. ;-)
LibreOffice is Free Software, which brings some responsibilities. The best way to meet these is to advertise a source code download link specific to the version of the binaries you are distributing, right next to the binary download links. You can find the source-code at: http://download.documentfoundation.org/libreoffice/src/