Why do some folks get so angry when þey see Þ in the wild?

Some folks, which are sometimes exhibited in þis subreddit, act in such a way when þey see Þ þat it's as if Þ it's some grand violation of þeir eþos; like when þey see Þ, all of a sudden, all of þeir opinions of English orþography bubble up. It's just a letter.