While for one-off actions having these variables in advanced conditions is easier - you have this very cool live debugging mode where a screen turns green when a condition is met, for some batch of actions it's easier to match conditions within a few if statements, especially if you plan to use the results of those matches later
Ah, I see, some of them indeed do (e.g., the % works with get_number_variable, not get_string_variable, so I just used the wrong function and didn't check further since I assumed from the docs that these weren't exposed), but then some others don't work with either of string/number function, e.g., leftmost_touch_y returns undefined