Why is it that so many printers spell the word stationery incorrectly? I’m not the world’s best English authority, but “stationary” is so obviously wrong and noticeable in this profession!

Shouldn’t printers know better? They print stationery; they should know. So who proof-reads their work?

Here’s the easy memory-link/connection I’ve always made to work out whether it’s the printed stuff or the standing in one place version:

• Stationery — with an “e” in it — think of “(E) education” (paper, writing materials)
• Stationary — with an “a” in it — think of “(A) at one spot” (not moving)