This might depend on where you live...my server pulls 180W average with 11 hard drives (10 reg, 1 SSD). That works out to ~$150/yr at my electricity rate of $0.0816/kwh.
Running a less efficient server or making a brand new server that consumes raw materials. Same can be said for a 10yr old Honda Civic versus a brand new Tesla. Either way is wasteful...just depends on your viewpoint.