The problem with travel planning isn't frequency of use: as other people have pointed out, Zillow and Cars.com are used infrequently but make money.
The problem is generating a consumer willingness to pay. Kayak has a commission on every sale, so their business model is baked in. But a travel planning site will need to get customers to pay extra, in some way, and they're reluctant to do so.
Travel planning is something that people have never paid for directly -- travel agents used to extract their fees invisibly -- so a travel planning company will either need to sell the travel themselves and collect commission like existing travel sites, or create a new market.
Zillow being used infrequently is an assumption. Real estate investors (and those that would like to be) use Zillow almost constantly because it offers some seriously helpful data that is vital to helping with good investment decisions -- and with real estate, you can never have enough data. I'm on Zillow multiple times per day. I also travel enough that I am Platinum in United, yet I have never used a travel planning site, nor do I actively look for one when getting ready for another trip. I use Trip Advisor for my preliminary hotel hunt, for restaurants. For attracticions, Trip Advisor works but so does a normal Google search. Travel Planning isn't 'painful' to me; at least not enough to use travel planning software. I just don't get the value or the problem it purports to solve. I do however, generally love TripIt Pro because there's nothing worse than looking for a confirmation number among multiple days worth of emails while standing at some counter or another. TripIt solves the very real problem of disorganized travel information. Before I used TripIt, I would have to hand-enter the ibro into my phone's Calender. But a travel-planning site? It would have to be really compelling to get me to invest the time to join yet another service. For 'challenging' destinations like India, it could be very valuable, but only if the quality of the information was better than I can find on my own through Google. There'd need to be more than just a bunch of third party APIs, there's need to be some original content. Trip Planning software is a hard sell because I don't find a week long trip to St Tropez or Austin that hard to plan.
Concur on that assumption. Real estate sites in general have a huge amount of passive traffic that can generate advertising revenue. Women in particular have a huge affinity to just browsing listings for fun and aspirational purposes. Whilst Zillow isn't ad driven, know a fair number of sites that rely on that. Source. Work in the space.
Any good real estate investor is accessing MLS listings directly, not browsing Zillow. I don't know anyone who takes Zillow's rent estimation or neighborhood trends numbers seriously, nor who scouts deals on their site.
It's a combination of frequency-of-use and pain-of-problem. You use Zillow infrequently, but when you do use Zillow, you're like, "Holy shit guys, this is my house! It costs hundreds of thousands of dollars and I have to live in it for years!" You're more incented to seek out really good tools.
The problem with infrequently used sites comes when the pain point is fairly small. Even if that pain is reduced a LOT by the site, down to almost nothing, if the absolute magnitude of the pain of the problem is low enough, it's just not worth it for people to hunt down their vague memories of a site and try it out and see if it's any good and learn its process. They'd rather accept the pain.
Zillow is an awful tool (data quality is infamously bad), but it is fun infotainment that gets eyeballs to hand over to agents, and those agents get a huge commission due to the oligopoly of real estate agent industry, so they can pay large referral/ad fees to zillow.
There are tons of travel affiliate programs, but none of them pay squat because the root problem is that "leads" are common, but paying customers are rare. It's a bit of an overgeneralization, but it isn't totally absurd to view the entire travel industry as a massive lead-gen operation for hotels and (to a lesser extent) airlines.
About the only thing you can do in travel is find some way to make something essential (housing, transportation) cheaper than it already is. If you can't do that, you're a middleman, and the game of the middleman is competitive and well-defined.
I'm in the market for a house now, and I use Zillow/Redfin every single day at the moment. I'm right there in the "I love this thing" state. I haven't purchased a home before, so it wasn't until now that I got to this point.
You're totally right that monetization is the next concern though.
In UK they even refer to this as "Property Porn" - people actually spend surprising amount of time looking at homes, since it's their biggest purchase, and largest asset. This is one of the reasons Zillow's USP was "estimates" - yet another reason to come back weekly and check how your home changed in value.
I guess the same could be true of travel planning, as well? Even though frequency of purchase is low (although not as low as a house), I can imagine the right kind of escapist travel planning site bringing back people every week to plan dream trips or vacations, however expensive or impractical.
The problem is generating a consumer willingness to pay. Kayak has a commission on every sale, so their business model is baked in. But a travel planning site will need to get customers to pay extra, in some way, and they're reluctant to do so.
Travel planning is something that people have never paid for directly -- travel agents used to extract their fees invisibly -- so a travel planning company will either need to sell the travel themselves and collect commission like existing travel sites, or create a new market.