One morning, when I was 17 or 18, I went to school, and every boy in the sixth form had received a Gillette razor in the post.
It must have been an expensive piece of marketing, but it was successful - I'm still using that razor handle more than 20 years later, and I'm sure I'm not the only one who’s ended up with some sort of brand loyalty, or at least brand inertia. The initial short term cost of sending those razors must have been made back many times over by the number of blades that the recipients will have bought over the years since then.
On the other hand, I haven't been suckered in by the razor blade absurdity that dominates that industry - that old razor handle still does a perfectly good job, and supposedly superior innovations haven’t made it obsolete. As long as they keep selling compatible blades, I’m unlikely to “upgrade”.