If it's a well known application I will go out of my way and buy it outside the store if that's the only way to get it. But for some random app that I just found I have to wonder if it's worth getting it from outside the store (and frequently the answer is no). I need to a) give my credit card to a random website that will probably get hacked in the next 12 months, b) start getting unsolicited email campaigns in about 18 months when someone hires a growth hacker, c) remember how to install the damn thing when I upgrade my laptop, d) deal with the reduced security guarantees of an app that did not go through the Apple review process and is not subject to the sandboxing of the App Store.

For many apps where I wouldn't mind spending $10 to $20 in the App Store, I am probably not going to deal with all of the above to buy it directly from the developer.