A glaring example:

Bargain: Inkjet Printers. You can get a very nice one for home use for $50 (US) and a powerhouse for $300 or so.

Ripoff: Inkjet cartridges. For best quality there is an advantage in using the printer manufacturer's cartridges (and paper), but with 2 to 7 cartridges in the set, at $30 to $80 per cartridge, good maybe for a couple of hundred pages per set, the ink becomes almost the entire cost of printing.

Packaging excess: HP packs two ink cartridges per package, total size of each cartridge about the same as a half-pack of cigarettes (for those who remember those). Each cartridge is in a hermeticly sealed plastic pouch, inside a small plastic coated cardboard box. At most retail outlets in my area, the pair of small cartridge boxes is in a larger heavy cardboard box, plastic coated, and then encased in a hard plastic "display pack" that's about 9" x 13" x 3.5" - made of plastic I can't cut with ordinary office scissors. I keep a pair of "Dutchmans" (compound lever aviation metal snips) at the desk just for opening ink packages. Each individual small cartridge box includes a "recycling envelope" and a large sheet of instructions urging you to "protect the environment by recycling your used cartridges." (And don't think about the 5 oz of non-biodegradable packaging it came in.)

Bargain: One of the local office supply chains gives me a free ream of paper for each used ink cartridge.

John