No, its much more about time/cost of labor analysis, copyright, and client security. To do the high-res texture pack, CCP would need to devote dev time to creating a method for the client resources to be loaded on the client's end depending on the texture packs available on the user's machine. Regardless of a person's ability to render the textures, CCP would need to handle multiple situations and provide debugging tools for cases where out-dated textures might affect client performance. Then CCP needs to devote additional dev resources to maintaining the regular textures that ship with the client, as well as the new high-res pack. In the end, CCP doubles their workload for each patch where even a slight tweak to an alpha layer is the only graphic change.

As well, adding methods to custom load a texture pack only increases the amount of information that the user can glean from the client's public-accessible data. The more you open up the client code to be poked around in, the more possible security holes you open for botters and nefarious ner-do-wellers to exploit the client. So, on top of the dev resources to maintain the texture packs with each release, you add additional dev time to security analysis.

Finally, adding the texture options will only lead to headaches down the road during code refactoring. Eventually, CCP will need to move up to DX11 as DX9 gets pushed out of the market (the day is nowhere soon, though). At that time, the engine will need some significant re-writing, if it's not already done. Anything that works with the graphics engine is going to need a fine-tooth combing to ensure compatibility, and a highres texture option will only present additional headaches during a full code review.

The highres texture pack would be awesome to have, but EVE isn't exactly like Skyrim et. al. where mods can just be dropped in willy-nilly. As an MMO, CCP has to make choices based on whether they can devote the dev time to maintaining the project in the long-run. We already saw the "classic" graphics option get dropped in favor of the Trinity engine for the same reason: dev time was being wasted maintaining old code and old graphics. It might be nice for the niche group that'd really like the high-res pack, but it's not really in CCP's best interests to devote the devtime to the project in the long run.