[jacobolus]

Because they turn out to be just as precisely fiddly as any other programming language, but deceptively appear not to be.

If you treat them as English you'll get burned. You have to still treat them as very precise formal languages where apparently trivial/irrelevant details are significant, and minor hard-to-spot mistakes will break your program.

Having more explicitly formal/structured syntax makes it easier to distinguish the different parts of the language, make sense of the details, and figure out what is or isn't allowed.

The best description I have for languages like this, e.g. Applescript, is that they are "read only languages" (in the opposite direction old-style Perl has been called a "write only language"): That is, if you have an already written program in hand it will be easier for a complete novice to read (at least, single isolated lines of code will be). But writing new programs is a huge pain in the ass.