Climbing gyms are tricky, but I think there are circumstances where they can make sense.
Rock climbing is indeed a great way to meet people. It's how I met my wife! And I have similar relationship stories from climbing friends; climbers tend to date each other a lot. For single people, it's definitely worth the cost if you're actually into climbing and being athletic.
Eventually, depending on where you live, you get good enough that the gym membership is no longer required and you can/would rather climb outside. Most outdoor climbing doesn't cost anything other than driving to the crag, and climbers tend to be pretty frugal people and like to camp instead of getting hotels. A bit more gear is generally required: a helmet, 1 rope per 2-3 people, some anchoring stuff if you're toproping, a set of quickdraws if you're leading. At this level, many people still keep the gym membership, but I think this gets hard to justify. I don't have a gym membership and only climb outside.
Gear cost to get started is pretty low for a technical sport, even at full price. The thing to remember is that the gear won't last: all soft goods (harnesses, cordage, webbing) have a max lifetime of five years because ozone and UV wears out the nylon, and that's just if you let it sit in a closet and never use it. Helmet foam similarly breaks down after a few years. Shoes wear out, how quickly depends on how often you climb. The real cost of climbing comes in when you've slowly accumulated lots of stuff over 2-3 years, then realize you're about to need to spend a bunch to replace the old items.
