I guess my reasons are the same as those described in the link above, i.e. it is a matter of dialect, my own dialect of English doesn't use "off of" and it sounds ridiculous to my ears; it produces a similar reaction to being confronted with mis-use of there/their/they're.
However, English is a very ill-behaved language, and "off of" just happens to be one of its irritating aspects I'll have to put up with.
However, English is a very ill-behaved language, and "off of" just happens to be one of its irritating aspects I'll have to put up with.