Actually, abbreviating words by eliminating individual letters, creating acronyms (IMHO -- or my favorite IMNSHO [in my (not so) humble opinion]) occurs any time in a culture where the "bandwidth" (how much space a message takes up) is expensive.

So, for example, Thomas Jefferson (who was writing in a time when mail was taxed according to how many sheets of paper were used -- and the recipient was expected to pay the postage) would often abbreviate "your" as "ur" -- just like the 'feckless' and 'sallow' youth of this generation (when cellphone users have to pay to receive calls and text messages -- sound familiar?). And you certainly wouldn't accuse Thomas Jefferson of being sloppy or careless with language, would you?

But I don't know, ymmv (your mileage may vary).