At home I use a stand or wall mounted bracket, it's easy to pick up the guitar, otherwise i have to get my guitar out of the case.
Why is it bad for your guitar?
If you play it regularly the dust won't get a chance, and after playing you can use a cloth to polish her.
It's also nice to look at your guitar when your not playing it.
Cases i use for transport and storage at stage so no one touches my instrument.