As others have said, I think it's mostly that hacked towns get a lot of attention for being unusual. Someone who doesn't hack is going to be more curious about a town with PWPs on the beach or bamboo in the river than a town that already fits the known format. Seeing something new can be refreshing and exciting, especially if you've been playing for a long time and have visited a lot of non-hacked towns. Hacking also allows players to do things that some non-hackers wish they could do—again, beach PWPs come to mind.
If I may be a little cynical, though, I think it's also because hacking has become pretty trendy on Tumblr. Even though AC was designed as a personal experience, it's become very community-oriented for many people (which is fine), and like any community, the AC community definitely has norms and trends. Certain villagers see huge spikes in popularity, and for a while, if you visit a lot of dream towns, you're seeing the same 25 villagers repeated over and over in almost every town. Certain PWPs are used regularly while others, even ones less bizarrely specific than the drilling rig, are virtually nonexistent. Pastel pink towns, rare Japanese unorderable items scattered throughout the dream town in wrapping paper, that doctor's mask clothing item . . . those are all very specific town choices that I've seen over and over and over again. For a while, I think hacking was also seen as a kind of status symbol, a way of being part of the Cool Club in the AC Tumblr community. Not that anyone was mean or deliberately exclusive, just that if you follow the trend, you gain more followers, get more integrated, etc. There's kind of a Look to some of the most popular towns, if you know what I mean.
Again, I want to stress that I don't think any of these choices are wrong or bad, and I'm definitely not saying that everyone who likes Marshal or has a fairy town is a mindless copycat. Lots of people just happen to enjoy those aesthetics! (And hey, if somebody creates a town just to be Tumblr-popular, that's fine too.) I just doubt that the community as a whole is immune to the influences of trends.