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.
A lot of good but also factually inaccurate reply. Electronics is 20-30% cheaper overseas compare to Thailand. So when you import electronics, either you will get charge 20-30% for shipping cost (Amazon, Ebay, etc, which will be the import tax equivalent), OR you will pay 20-30% import taxes upon delivery. The delivery man will come to your house to tell you to go to the office to get your package. The high tax is probably to protect Thai companies that sell the same product 20-30% more expensive. If it was so cheap to import electronics, nobody would buy from Thai store.