Though nobody is likely to believe me, the point is to make products so solidly that don't need to be repaired. Apple doesn't make a fortune on repairs, it makes a fortune by avoiding repairs. Within the warranty period, hardware failures are Apple's cost, not the customer's. It's not about screwing the person who breaks his stuff, it's about a happy experience for those who don't.
Do people want their devices to be less susceptible to water damage? That means sealed assemblies, and properly re-sealing them after repair. Screws can come loose, glue does not. Connectors that can withstand repeated hand insertion/removal cycles by the average consumer are bulkier and more expensive than those that are intended to be handled once or twice by trained personnel or machines. And tamper-resistant screws not only tell a repair shop that some gorilla worked on the thing, they send the same warning to potential buyers of used gear.
I wouldn't buy a mechanical watch that had screwdriver pry marks where the back meets the case, and I certainly wouldn't buy a computer or iPhone that had equivalent damage. It's very likely there will be more damage inside. Anyone who won't spend $10-$20 on the right tool is someone who has no business making a repair in the first place - the first priority is to do the repair right, not do it cheap.