For a native speaker? Not necessarily. There are many regional accents where the 'g' is silent or minimised: for example, the traditional Cockney speech of London, or the accents of some southern states of the US. For native speakers from these areas, this is a normal way to speak. Something which is normal is not 'bad practice'.
For you as an English learner? Yes. Learners of English should learn and use standard pronunciation.