Is it advisable to add peers or colleagues to research projects as co-authors with little or no inputs to cushion or push them up in the field of academia?
I agree. If someone has made a contribution it should be acknowledged, but gift authorship is not appropriate. It's also hazardous for the person added: there have been recent examples of scientific fraud that have caused co-authors major problems. See, for example - https://ost.openum.ca/files/sites/132/2017/06/JASIST_MongeonLariviere.pdf