They don't care. There are thousands of DTVs being issued for a whole range of reasons. You really think they're going to follow up every single visa, to make sure people are keeping their dental appointments, to make sure digital nomads really are sitting in coffee shops playing computer games, to make sure people are turning into master chefs? Seriously?
I thought you just paid for a month's course, got the visa, then when you get here you hurt your leg and cancelled the course. I mean isn't EVERYONE getting these visas? 😆😆
Seems you're not the sharpest knife in the kitchen drawer. Thailand doesn't always operate within its own legislation. You are aware prostitution is illegal in Thailand? You are aware bribing a government official is illegal? Not wearing a crash helmet when riding a motorcycle is illegal? Riding motorcycles on the footpath is illegal? Come on, wake up.