If you've got a 'fake' christmas tree, then absolutely display that thing every year for at least twenty years to lessen the environmental impact without the fire risk of bringing a real tree without roots indoors.
I grew up with a plastic Christmas tree. It doesn't go up every year in my parent's house. I was pretty happy to see my parents pose with it this year. It's now 35 years old.
There is a company that tried this as a start up actually. You'd adopt a tree, they'd deliver it in a big pot, then haul it back up a field after Christmas. It came marked so you'd get the same tree every year until the pot was too small, then they'd permanently plant it and give you a new tree.
It's a good idea but more expensive than I'd like, so fake tree for 20 years it is.