There was a project a few years back that scrapped and parsed, literally the entire internet, for recipes, and put them in an elasticsearch db. I made a bomb ass rub for a tri-tip and chimichurri with it that people still talk about today. IIRC I just searched all tri-tip rubs and did a tag cloud of most common ingredients and looked at ratios, so in a way it was the most generic or average rub.
If I find the dataset I'll update, I haven't been able to find it yet but I'm sure I still have it somewhere.
So I rarely splurge on an app but I did splurge on AntList on Android because they have a import recipe function. Also allows you to get paywall blocked recipes if you are fast enough.
I use them hundreds of times daily. I'm 3-5x more productive thanks to them. I'm incorporating them into the products I'm building to help make others who use the platform more productive.
Why the heck should I not use them? They are an excellent tool for so many tasks, and if you don't stay on top of their use, in many fields you will fall irrecoverably behind.