They all have uniforms for school but not 3 I grant you .isn't a uniform to make all kids equal ,not allowing those with money to look better in designer cloths.
I don't understand why kids need 3 when I was in the Cubs and Scouts in the uk we only had one uniform it did for all occasion even High Church parade once a month.
This certainly is not the teaching of the world wide scout association. Plus it's a catholic order not a Buddhist one so I guess Thailand can make it's own rules as it cannot be recognised buy the world scout organisation as defined by Baden Powell .