You are lucky to not get sued, because they have ground to sue given the misinformation of your review. Thai laws are very strict regarding defamation. Most school are similar to the one you ran into. You can't compare with University, but what you described is pretty standard (cost wise). For example, the 1.9k baht every 3 months is mandatory.
Which website did you buy the laptop from? Thailand has deals with many websites (including Amazon and Ebay), where they will charge 20-30% for delivery fees which replace the typical import taxes. A lot of people don't notice this upon buying online. So no, a company shipping fee is not only their "own business", it is country specific and based on many things depending on the product.
I am giving accurate and verifiable information. As proof of that, go to Amazon right now and try to buy a Laptop, you will see upon buying that the delivery fee will be 20-30%. So if you buy a 1k USD Laptop, you will get charged $200-300 USD in shipping cost. This is because Thailand have aggreement with such famous website to use shipping cost as taxes. But for websites without such agreement, they will charge you upon delivery. You can try yourself :). This is why electronics is 25-30% more expensive in Thailand.